Heritage Assessment
Invincible Battery
NZAA Site No. E40/58
Invincible Concentrator
NZAA Site No. E40/59
Peter Petchey
Southern Archaeology Ltd
2014
Invincible Mine Complex Heritage Assessment
Cover Photo: The Invincible water wheel in 2014.
Peer review statement
Assessment prepared by Peter Petchey, Southern Archaeology Ltd., Dunedin.
Date: 2014
Assessment reviewed by Neville Ritchie, Department of Conservation, Hamilton.
Date: 19/12/2014
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Invincible Mine Complex Heritage Assessment
Table of Contents
1.0! Site Overview ............................................................................................................ 4!
2.0! Setting ........................................................................................................................ 6!
3.0! History of the Invincible Mine .................................................................................. 8!
4.0 ! Physical Description ................................................................................................ 18!
5.0! Cultural Connections ............................................................................................... 40!
6.0! Contextual Analysis ................................................................................................ 42!
7.0! Assessment of Significance ..................................................................................... 47!
7.1 Historic Significance ............................................................................................. 47!
7.2 Physical Significance ............................................................................................ 48!
7.3 Cultural Significance ............................................................................................. 49!
8.0 Comparative Analysis .............................................................................................. 49!
9.0 Sources & reports...................................................................................................... 52!
10.0 1995 Photos ............................................................................................................. 54!
11.0 Other Data ............................................................................................................... 61!
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Invincible Mine Complex Heritage Assessment
1.0
Site Overview
AMIS Functional Location number: DS-38-105-5007
AMIS Equipment number: Water wheel 49570; Concentrator 49572; Berdans 49573.
The Invincible Mine and Battery and the associated Otago Pyrites Saving Company’s buddle
(also referred to as a ‘rotating convex table’ and a ‘concentrator’) are located on the western
flank of the Richardson Mountains (which in turn defines the eastern side of the Rees Valley)
about 17 kilometres north of Glenorchy. The gold mine opened in 1880, and operated
intermittently until the mid-1890s, with sporadic prospecting continuing until about 1937.
The sites are notable for the intact set of seven Berdans at the battery house, which is the
largest surviving array of Berdans in New Zealand, and the buddle on the valley floor, which
is the most intact gold-saving buddle in New Zealand. The sites are also set in a spectacular
alpine landscape.
The Invincible Mine Historic Reserve is within the Wakatipu Area of the Department of
Conservation. It is an actively managed site, which consists of overshot water wheel (1882),
stamper battery (1882), concentrator (1884) and Invincible Berdans (1886). The Invincible
Battery and associated sites have been recognised as significant by the creation of a historic
reserve to protect them, and by inclusion in a number of lists and schedules of significant
and/or protected features, which are described below.
The Invincible Mine and Battery and associated Otago Pyrites Saving Company buddle are
situated within the Invincible Mine Historic Reserve (NZ Gazette 1979 p.570). This reserve
in in two parts:
• Invincible Mine: Section 1 Block XII Earnslaw SD, S.O. 18563 (Invincible Mine
Historic Reserve).
• Invincible Buddle: Section 2 Block XII Earnslaw SD, S.O. 18563 (Invincible Mine
Historic Reserve).
However, during the preparation of this heritage assessment and the updating of the NZAA
records, the GPS co-ordinates for the buddle appear to indicate that the surveyed boundaries
of the lower section of the reserve (Section 2 Block XII Earnslaw) lie a considerable distance
from the actual archaeological features (Figure 1). This will need to be checked by a qualified
surveyor and the situation resolved if there is a problem.
The Invincible Mine and Battery and associated Otago Pyrites Company buddle are listed by
Heritage New Zealand:
• Invincible Mine & Battery (List No, 5603) as a category 2 historic place.
• The Invincible Buddle (List No. 5604) as a category 2 historic place.
The Invincible Mine and Battery, Otago Pyrites Company buddle, and associated sites are
recorded as archaeological sites on the New Zealand Archaeological Association Site Record
File (Archsite) (Figure 2). These records have been updated as part of this Heritage
Assessment:
• Battery NZAA Site No. E40/58 (S123/253).
• Buddle NZAA Site No. E40/59 (S123/254).
• Invincible Mine Machine Level drive Site No. E40/63.
• Invincible Mine upper workings Site No. E40/64.
• Hut ruin at start of Invincible track Site No. E40/65.
• Log hut beside Invincible track Site E40/66.
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Invincible Mine Complex Heritage Assessment
The Invincible Mine and Battery and associated buddle are listed in the Queenstown Lakes
District Council District Plan in Appendix 3 Inventory of Protected features:
• Invincible Mine, Appendix 3, Item 34, QLDC category 3.
• Invincible Battery, Appendix 3, Item 703, QLDC category 2.
• Buddle, Appendix 3, Item 704, QLDC category 2.
Figure 1
Annotated GIS map (QLDC online GIS), showing the location of the main features of
the Invincible Mine complex and the current reserve boundaries.
Invincible Mine Area
1:9,028
October 6, 2014
Pending
Inactive
0
0.075
0
0.1
0.15
0.2
0.3 mi
0.4 km
Land Information New Zealand & Eagle Technology Group Ltd
Approved
peterpetchey
Figure 2
The Invincible Mine complex sites as recorded in the NZAA Archsite database
(www.archsite.org.nz)
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Invincible Mine Complex Heritage Assessment
2.0 Setting
The Invincible Mine and Battery are located at about 820m asl on the western flank of the
Richardson Mountains, above the valley of the Rees River, about 17 kilometres north of
Glenorchy and the head of Lake Wakatipu (Figure 3). The associated buddle is found on the
valley floor almost directly below the battery site. A Department of Conservation walking
track follows the old mine track up from the valley floor. The return trip takes approximately
3 hours, and involves climbing and then descending approximately 400 metres. Table 1 gives
the NZTM co-ordinates for the main features of the complex as recorded in the New Zealand
Archaeological Association Site Record File (all updated in 2014 as part of this assessment).
Figure 3
The location of the Invincible Mine, Battery and Buddle (NZTopo50 CB10 Glenorchy).
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Invincible Mine Complex Heritage Assessment
Table 1
Hand-held GPS co-ordinates for the recorded sites associated with the Invincible Mine
(co-ordinates are in NZTM).
Description
Invincible Battery
Otago Pyrites Co. buddle
Machine Level Drive
Invincible Mine
Hut at track start
Log hut by track
NZAA No.
E40/58
E40/59
E40/63
E40/64
E40/65
E40/66
Easting
1241258
1240540
1241238
1241438
1240285
1240809
Northing
5037661
5037774
5037510
5037579
5036929
5037356
The walking track starts at the road in an area of mixed grassland and beech forest, and then
climbs steeply in a zig zag up to the battery and mine site. On the way it passes through
several areas of thick regenerating scrub and stands of beech forest. The battery and mine
sites are in an area of mixed grassland with patchy scrub that is slowly encoraching on the
entire area. The Berdans have been kept clear, and the main walking track to the site is clear,
but other features such as the collapsed stamp mill are becoming increasingly overgrown. In
several places along the walking track to the Invincible site, and from the battery and mine
sites themselves, there are spectacular views up and down the Rees Valley (Figure 4).
Figure 4
View looking across the Invincibe Battery terrace and up the Rees Valley.
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Invincible Mine Complex Heritage Assessment
3.0
History of the Invincible Mine
Gold was first discovered in the Wakatipu region in 1862, and Mining Surveyor Wright
commented in 1863 that “very few places have been prospected within this district that have
not been found to contain some traces of gold” (AJHR 1863 D6:18). The Invincible Reef was
discovered in 1879, but who exactly should have the credit is uncertain: Chandler (1984: 28)
stated that local tradition had always credited a local shepherd, Tom Hope with the discovery;
while Sutherland (1973: 1) stated that it was found by two shepherds, W.T. Campbell and W.
Rainer. The Invincible Prospecting Company was soon formed to test the ore, and small
quantities of ore were sent to Wellington in March 1880 for test crushing, which proved
encouraging (AJHR 1880 H26: 27). The Invincible Quartz Mining Company (with a capital
of £21,000) was formed in 1880 by W.L. Davis, C.C. Boyes, R. Williams, J.E. Davis, S.W.
Wilson, W. Rainey and T. Hope, (AJHR 1888 C5: 44; Chandler 1984: 28; Sutherland 1974:
2).
In 1882 the Invincible Company erected a ten-stamp battery, each stamp weighing 8 cwt.,
driven by an overshot water wheel. Gold saving was by blanket tables, with the concentrates
washed out from the blankets afterwards ground in a Berdan. No copper plates or mercury
wells were used (AJHR 1885 C2: 11). The machinery was manufactured by Thompson & Co.
of Castlemaine in Australia, and the total cost of the battery, water race and associated work
was £1737 16s 8d (Otago Witness, 17 May 1884: 12; 14 June 1884: 9). Contemporary
photographs show that the entire plant, including the water wheel, was housed inside
weatherboard buildings (Figure 5). The first stone was crushed in December 1882, but this
yielded only 325 oz. of gold from 1,350 tons of stone, and the reef appeared quite disjointed
and broken (AJHR 1883 H5: 40). Although returns subsequently improved, (2,226 oz. from
3,173 tons in 1884), the company was losing a large amount of gold through the battery due
to the high pyrites content of the lode. In order to quantify this loss Professor Black of the
Otago School of Mines carried out an assay of the tailings that returned over 11 oz. to the ton
from the pyrites.
In 1885 the Invincible Company entered into an agreement with George Watson of Dunedin
(the Otago Pyrites Saving Company Ltd.) to allow him to work all of the tailings from the
battery for a period of three years (or 4 or 5 years, depending on the source quoted) on
consideration of 15 per cent of the gold that the pyrites contain (AJHR 1885 C2: 11; Otago
Witness 4 April 1885: 22; 13 June 1885: 13). The Pyrites Company erected a new works on
the floor of the valley, with a 2,200 ft. flume to carry the tailings down from the Invincible
Battery above. The pyrites saving works consisted of two classifiers, three pyramidal boxes,
two jiggers and a 26 feet diameter “rotating convex table,” driven by a 10 inch diameter
“Little Giant” turbine, all housed in a building that measured 45 feet by 90 feet (AJHR 1886
C4: 22; Otago Witness, 27 August 1886: 12). The machinery was imported from Germany,
and was set up under the supervision of J.B. Neal, and the pyrites that were saved were
shipped to the Sandhurst Pyrites Works in Victoria for smelting (Otago Witness 2 January
1886: 14; 27 August 1886: 12). An extremely detailed account of the plant and process was
published in the Otago Witness (27th August 1886, p. 12), and this is reproduced here in
Section 11.
However, to check Professor Black’s assay the Invincible manager, Alfred Morrisby,
collected 11 ! tons of pyrites, ground it in a Berdan, and got 108 oz. of retorted gold. This
return led the company to order six additional (to make a total of 7) 4 feet 6 inch Berdans
from Kincaid McQueen & Co., at a cost of £1,230, to further process their tailings and
recover the gold they were losing (AJHR 1886 C4: 22; C4A: 29). For the year from March 31
1885, the average yield per ton was 9 " dwt. The following year the average yield was 14
dwt. per ton (AJHR 1887 C6: 37) (such figures are, of course, affected by the quality of stone
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Invincible Mine Complex Heritage Assessment
being crushed at the time). The improved processing of the ore by the Invincible Company
left little for the Otago Pyrites Saving Company to recover, and it folded in 1886. The “Little
Giant” turbine was later moved to power a battery in Butcher’s Gully, Skippers (AJHR 1889
C2: 58).
Figure 5
The Invincible Battery (New Zealand Mining Handbook 1906).
Figure 6
Detail from an 1896 survey plan showing the battery house and associated buildings at
the Invincible Mine (Land Information New Zealand, SO 4147).
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Invincible Mine Complex Heritage Assessment
Figure 7
One of the Invincible Mine drives in the 1880s (Burton Bros. photo, Lakes District
Museum EL 1226).
Although the Invincible Company had improved its gold saving, bad luck followed, and the
reef was lost in August 1887. In February 1888 the mine was let on tribute for three years, the
tributors to pay 16% of the gross yields (AJHR 1888 C6: 36; 1889 C2: 57). In the first year
the results were encouraging and 500 oz. was extracted, but nothing was found subsequently.
In 1891 the mine was sold to the Invincible Quartz Company (also named in the annual Mines
Department reports as the Rees Valley Quartz-mining Company Ltd.) who proceeded to
prospect the old claim and erect pumping machinery to enable them to test deeper levels
(AJHR 1891 C4: 52, 182). But despite several years work on the part of the new company,
the reef was not relocated.
The American mining expert T.A. Rickard visited the Invincible Battery in the 1890s, and
commented unfavourably on the battery operation. Attempts to improve gold recovery by
adding mercury to the mortar box had not been successful, but rather had apparently caused a
loss of gold. Rickard was of the opinion that this was due to the design of the mortar boxes,
which were “merely square iron boxes. He commented that they were “not designed of a
shape adapting them for amalgamation inside, and there was no opportunity given to the
amalgam to collect out of reach of the falling stamps, but, on the contrary, the quicksilver
added was subjected to a violent agitation which caused it to be floured-that is, broken up into
a myriad of small globules. These are readily borne away by the water, and escaping with the
tailings, also take with them a certain amount of gold with which they may have come in
contact’ (Rickard 1898: 191).
A further attempt to re-process accumulated tailings was made using cyanide, and a treatment
plant consisting of one solution tank, two 25 ton leaching vats, two extractors and two sumps
was built in about 1896, but this also failed and was abandoned by 1897 (AJHR 1897 C3:
123; O.G.P. 1981). The battery, which was still standing but not in use at this date, was
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Invincible Mine Complex Heritage Assessment
described as a ten stamp mill, with 800 lb. stamps, seven 4ft. 6in. Berdans, an octagonal iron
amalgamating barrel and a shaking table (AJHR 1897 C3: 123).
The claim was taken up again in 1903, when some more prospecting was done, and once
again in 1913 by a Melbourne syndicate. Nothing came of either of these ventures (AJHR
1903 C3: 169; 1904 C3: 120, 1913 C2: 47; 1914 C: 63). In 1922 Thornton and Fitt again
prospected the mine, putting in a drive to the south-west of the old workings (AJHR 1923 C2:
23). More attempts to reopen the mine were made during the Depression of the 1930s; in
1931 the Rees Valley Mining Syndicate received a £40 subsidy for driving (AJHR 1932-33
C2: 230); in 1934 a party of three men were subsidised to prospect for scheelite in the vicinity
(AJHR 1935 C2: 40); and in 1937 prospecting operations were carried out to north of the old
Invincible Mine (AJHR 1938 C2: 43). In the post-war period prospecting work continued,
and a map held by the late Mines Inspectorate office in Dunedin showed the locations of
Wathersonton’s reef and a number of camp sites, adits and bulldozer excavations (Figure 8).
The track up to the Invincible Battery was probably also recut using a bulldozer to improve
access to the area (Sutherland 1973: 6).
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Invincible Mine Complex Heritage Assessment
Figure 8
Map of Watherston’s Reef & Environs, drawn by A.R. Mutch (not dated) (ex. Mines
Inspectorate Office, Ministry of Commerce, File 12/46/1187).
When the Invincible Mine and Battery were closed much of the machinery was abandoned on
site, and photographs from the 1930s onwards show the water wheel and Berdans still intact
(but slowly decaying), and the battery frame standing with the camshaft in place, but the
stamps, guides and mortar boxes were all missing (Figures 9 to 12). Down on the valley floor
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Invincible Mine Complex Heritage Assessment
the convex table was left in place, but all other machinery had been removed. In 1983 the
Department of Lands & Survey replastered the table’s convex upper surface. By the mid1990s the water wheel had largely collapsed, and the Berdan framework was very decayed
(Petchey 1995). In 2001 the Department of Conservation retimbered the Berdan framework
using macrocarpa timber (Otago Daily Times 11 May 2001).
Figure 9
The Invincible Battery and Water Wheel, mid twentieth century (D. Sharpe, Lakes
District Museum EL 5683).
Figure 10
The Invincible Battery in 1985 (Queenstown & District Historical Society, Lakes District
Museum EL 6439 a).
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Invincible Mine Complex Heritage Assessment
Figure 11
The Invincible water wheel in 1985 (Queenstown & District Historical Society, Lakes
District Museum EL 6439 c).
Figure 12
The Invincible Berdans in 1985 (Queenstown & District Historical Society, Lakes
District Museum EL 6439 b).
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Invincible Mine Complex Heritage Assessment
The Rees Gorge Gold Mining Settlement
An industrial enterprise such as the Invincible Mine and Battery and associated pyrites saving
works employed many men, some of whom had families. The Rees Gorge gold mining
settlement was a somewhat scattered collection of houses and huts, and was the subject of
Arthur Sutherland’s research in 1973 (Sutherland 1973). His map (Figure 13) shows the
location of the store/post office and generalised position of some of the hut sites.
Figure 13
Map of the Invincible Area by Arthur Sutherland (Sutherland 1973). This shows the
locations of some of the huts associated with the mining ventures in the area.
The Invincible Mine employed about six men in 1880, and reached a peak of about 30 to 35
in the mid-1880s, while the Pyrites Company employed 6 men, and census data shows that
almost 60 people were living in the Rees Gorge area in 1891 (Table 2) (Sutherland 1973: 6).
An 1896 plan of the mine (Figure 6 above) shows that the managers’ house was close to the
battery, and several huts were nearby. As the archaeological evidence (discussed below)
shows, there were a number of other hut sites around the battery and mine, and Sutherland
(1973: 7) has estimated that some 20 to 25 huts existed in the Rees Gorge settlement. Many
miners would have lived there in the summer months, but during the harsh winters it is likely
that most would have decamped to Glenorchy or further afield (Sutherland 1973: 7). A store
was opened by John McDougall in about 1884 near the bottom of the Invincible Road, and
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Invincible Mine Complex Heritage Assessment
between 1885 and 1888 it also served as the Rees Gorge Post Office (AJHR 1886 F1: iv;
1889 F1: v; Sutherland 1973: 7). An undated photograph of the Invincible Mine (Figure 14)
also shows a house close the battery together with another house on a spur to the north of the
battery, in a location that has yet to be checked for archaeological evidence (although the
NZTopo50 CB10 Glenorchy map shows a structure in this location).
Table 2
Census data for Rees Gorge (Sutherland 1973: 10).
Year
1881
1886
1891
Total
48
59
Males
44
28
Females
4
31
Figure 14
An undated images of the Invincible Battery (left mid ground) and the house on the
ridge above the Invincible Creek (Lakes District Museum EL 5682). It is notable that
the water wheel is in the open, meaning that this photo was taken either during the
construction of the battery, or after its abandonment.
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Invincible Mine Complex Heritage Assessment
Chronology of the Invincible Mine Complex
1862
1879
1880
1882
1885
1886
1886
1886
1887
1888
1891
1896
1903
1913
1922
1931
1934
1937
1979
1983
1989
1995
2001
2014
17
Gold discovered in the Wakatipu region.
Gold-bearing reef found in the Richardson Range.
Invincible Prospecting Company formed.
Invincible Quartz Mining Company formed to work the reef.
Ten-stamp battery powered by overshot water wheel was erected.
First stone crushed for disappointing yield: 325 oz from 1350 tons of stone.
Agreement with Otago Pyrites Saving Company to retreat the battery tailings.
Pyrites Company erected saving plant including ‘rotating convex table.’
The Invincible Company installed 6 additional (to make total of 7) Berdans.
Improved gold recovery left little for the Pyrites Company, and it folded.
Reef lost.
Invincible Mine let on tribute.
Mine sold to the Invincible Quartz Company, which erected pumps and prospected.
Cyanide plant erected to reprocess tailings. Failed and abandoned the following year.
Claim was prospected.
Claim was prospected by Melbourne syndicate.
Thornton & Fitt prospected the mine and dug new drive.
Rees Valley Mining Syndicate carried out subsidised work.
Scheelite prospecting in the area.
Prospecting.
Invincible Mine Historic Reserve gazetted.
Buddle replastered by NZ Lands & Survey.
Detailed drawings of Berdans commissioned from Works Consultancy Services.
Peter Petchey commissioned to produce conservation plan.
Berdans retimbered by DOC.
Peter Petchey commissioned to produce Heritage Assessment (this report).
Invincible Mine Complex Heritage Assessment
4.0
Physical Description
As described above in 2.0 Setting, the Invincible Mine and Battery are located on the
mountainside, with the buddle on the valley floor below. The old Invincible track is now used
as a walking track to the upper section of the historic reserve (Figure 15).
Figure 15
Otago Goldfields Park map of the Invincible Mine Historic Reserve. Note that this map
does not show the upper mine workings (see Figure 16 below).
The Invincible Battery site and Otago Pyrites Saving Company Buddle have been visited and
photographed by the present author on three occasions; in April 1993 as part of an MA
research programme (Petchey 1996); in April 1995 for the preparation of a conservation plan
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Invincible Mine Complex Heritage Assessment
(Petchey 1995); and in October 2014 in order to update the site description for this heritage
assessment. Between the two latter visits, in 2001, the Department of Conservation
retimbered the framework for the row of seven Berdans (the work was actually carried out by
Heenan Consulting Ltd.). A selection of 1995 photographs of the sites are included here in
Section 10. The 2014 images are incorporated into the site description below. Detailed
drawings of the Berdans were prepared by Works Consultancy Services in 1989.
However, no systematic survey has been done of the archaeological evidence of the
Invincible Mine complex, and so there is no detailed map and no comprehensive description
of the overall site and all of its components. The preparation of such a map was outside the
brief of the present and past reports, but would considerably assist in the interpretation and
management of the site. The map used here (Figure 16) is simply based on a Google Earth
overlay, and is only a sketch plan showing the main features. Comparison of Figures 15 and
16 shows that the upper mine workings are not included in the Invincible Historic Reserve.
Figure 16
Map of the main features at the Invincible Mine and Battery. Based on Google Earth
overlay.
Description of Main Features
The Invincible Company's mine and battery sites are located at an altitude of 820 metres asl
on the east side of the Rees Valley, about 16 kilometres from the head of Lake Wakatipu.
They are reached by walking up the Department of Conservation track that follows the old
mine access road from the floor of the valley. The site of the Pyrites Company’s works, which
includes the circular buddle, is on the floor of the valley almost directly below the battery site.
Associated with the mine complex are a number of huts sites and the mine road itself,
together with a number of features associated with later attempts to mine the area. The sites
are described below in geographical order, starting at the mine and heading downhill to finish
at the Pyrite Company’s works.
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Invincible Mine Complex Heritage Assessment
Invincible Mine
The upper workings of the Invincible Mine are located on mountainside above the battery
site, and the Machine Level adit is located 150 metres to the south and just above the battery
site. This archaeological evidence agrees with historical accounts that described ‘upper and
machine-site levels’ (AJHR 1887 C6: 38). The most visible evidence of the mining activity
are the numerous mullock heaps that mark where underground workings once existed (Figure
17), although with the exception of the Machine Level adit all of the drives have now
collapsed. The Machine Level is still partially open, and has been gated to prevent anyone
from entering the adit (allthough the drive is now completely collapsed only a feet feet from
the entrance). Other surface features that still survive include a tramway cutting with stone
revetment (Figure 18), the benched tramway formation between the Machine level and
Battery, and the remains of a stone building beside the Machine Level adit.
Figure 17
Looking up to two of the main mullock heaps of the upper workings of the Invincible
Mine in 2014.
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Invincible Mine Complex Heritage Assessment
Figure 18
Stone revetment along the tramway cutting to one of the upper Invincible Mine drives
(collapsed) in 2014.
Figure 19
The entrance to the Machine Level drive in 2014. This level was driven in 1886 (AJHR
1886 C4: 22).
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Invincible Mine Complex Heritage Assessment
Invincible Battery
The Invincible Battery site is located on a terrace on the mountainside below the mine
workings. The battery site itself consists of the the water wheel remains, the stamper remains
and the row of seven Berdans (Figure 20), while the wider terrace also includes the Machine
Level tramway and drive, and the sites of numerous huts and buildings (see Figure 30 below).
Figure 20
The Invincible Battery site in 2014, showing the Berdans to the right and the collapsed
stamp mill to the upper left.
The layout of the battery site is conventional for a gravity-fed system, with the main
components arranged down the slope. The ore was transported to the top of the site (either
from the upper workings or the Machine Level via the Machine Level tramway), was crushed
in the 10 stamp mill, passed over the tables, and then the concentrates were further ground in
the Berdans. The water wheel was located above and to one side of the stamp mill, and drove
the machinery through flat belts (as evidenced by the several wide pullies still on site).
The Stamp Mill
The collapsed timber frame and the camshaft of the stamp mill remains on site, together with
a scatter of smaller items (Figure 21). There were originally ten stamps weighing 8 cwt. each
(AJHR 1885 C2: 11). There is no evidence that this arrangement was modified during the life
of the battery. Photographs of the abandoned battery taken throughout the twentieth century
(Figures 9 and 10) show that the main stamper frame was left in place with the camshaft still
mounted, but the stamps, guides and mortar boxes were all removed at or soon after
abandonment. The frame had three vertical kingposts and two trestle frames (one on each end
of the structure). The two outside camshaft bearings were carried on the horizontal beams of
the trestle frames, while the centre bearing was mounted on the centre kingpost. The timber
frame is still present, but has decayed badly and collapsed forward under the weight of the
camshaft.
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Invincible Mine Complex Heritage Assessment
Figure 21
The Invincible stamp mill in 2014.
The camshaft is fitted with a large iron drive pulley at one end, and a smaller timber pulley at
the other. The large pulley would have been the main drive from the water wheel (almost
certainly via intermediate shafting), and the the small pulley would have then taken drive to
ancillary equipment. The camshaft drive pulley is of an unusual design, with curved sheet
iron spokes and a cast iron hub, and a larger pulley of exactly the same pattern is lying nearby
(Figure 22). It is almost certain that both were made by the same company, most likely
Thompson & Co. of Castlemaine who supplied the original battery equipment (Otago
Witness, 17 May 1884: 12; 14 June 1884: 9), and they were both part of the original 1882
battery equipment.
The cams are of a conventional design, being reasonably heavy but without any strengthening
webs, and are fixed with keys in a cut keyway. They show only moderate wear on their faces.
They are set to give reciprocal drop orders: the left hand bank are set for 1-4-2-5-3, and the
right hand bank are set for 1-3-5-2-4. This was a common drop order that was used in South
Africa and the USA, and is the most common order found in surviving New Zealand stamp
mills (Petchey 2013: 112, 225).
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Invincible Mine Complex Heritage Assessment
Figure 22
The large (54 ! inch diameter) pulley lying on the ground near the Berdans in 2014. It is
exactly the same style as the camshaft drive pulley on the stamp mill, and was therefore
probably part of the original battery equipment that was manufactured by Thompson
& Co. of Castlemaine.
Scattered in front of the stamp mill are fragments of perforated iron sheet from the mortar box
screens. The sheet is punched with 168 holes per square inch, each hole being approximately
1/32 inch diameter. This is very similar to the punched iron screen material found at the
Premier/Maryborough Battery site (F41/471) at Macetown (Petchey 2013: 216), but is finer
than the range that Gordon (1906: 386) stated was generally used in New Zealand. This
would indicate that the battery was set to crush the ore quite finely. There were also some
fragments of sheet iron with much larger " inch (6.4mm) holes, the function of which is
unknown; these holes are far too large to be used as mortar box screens under normal working
arrangement.
Overall, the surviving evidence shows that the Invincible stamp mill was a mid-weight ten
stamp mill with a timber trestle frame. The machinery was supplied from Castlemaine in
Australia, and although slightly unusual in detail it was conventional in overall design and
layout. The surviving screen fragments indicate that it was set for fairly fine crushing
(although this evidence can only provide a single snapshot in time).
Berdans
The row of seven Berdans are the most notable feature of the battery site, as this is the largest
set of Berdans to survive in New Zealand (Figures 23 and 24). They are mounted on timber
framing set in a stone-lined pit in front of the stamp mill. There is a common drive from
below, with an arrangement of dog clutches whereby individual Berdans could be engaged or
disengaged. Each Berdan had (and most still have) a cast-iron trough mounted around the rim,
which discharged at the low point (Berdans were always mounted on an angle) into a
collection trough which is no longer present. When recorded in 1995 the Berdan framing
timber (identified as local beech1) was badly decayed, and in 2001 it was replaced by the
Department of Conservation. Macrocarpa (Monterey Cypress) was used in place of beech in
the reconstruction (Otago Daily Times 11 May 2001).
1
Identification carried out by R. Wallace, Auckland University.
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Invincible Mine Complex Heritage Assessment
Figure 23
The seven Invincible Berdans in 1995. This shows the Berdans with their original beech
framing. This has since been replaced by the Department of Conservation.
Figure 24
The Invincible Berdans in 2014. This
shows the replacement macrocarpa
framing that was constructed in 2001.
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Invincible Mine Complex Heritage Assessment
Figure 25
Detail of one Berdan in 2014.
The surviving archaeological evidence nationwide indicates that under-driven berdans were
far less common that top-driven berdans, but other examples do exist, such as the pair at the
Croesus Battery at Lyell (site L29/2). However, the number of Berdans at the Invincible site,
and their intact state (albeit now with replaced framework) makes them unique in New
Zealand.
Water Wheel
The water wheel was a wooden structure with iron axle and hub, fed by a water race from
Invincible Creek. Photographs taken in the mid-twentieth century show the wheel standing
intact (but with the ring gear removed), but by the 1980s the above-ground structure had
largely collapsed. By 1995 only one spoke remained erect above the hub, and now (2014) no
above-horizontal timbers remain in place (Figure 27). Down in the stone-lined wheel pit the
lower section of the wheel survives in better condition (albeit covered with the debris from
the upper half).
The wheel support walls and wheelpit are constructed from stacked schist, and remain in
relatively good condition. Photographs of the intact wheel show that it was an overshot wheel,
and as there is no ground-level tailrace to discharge used water, there must be a tailrace tunnel
running from the base of the wheelpit. However, the route and condition of this tunnel is not
known.
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Invincible Mine Complex Heritage Assessment
Figure 26
The Invincible water wheel in 1995 (P. Petchey). At this date only a few of the abovehorizontal spokes remained in place.
Figure 27
The Invincible water wheel in 2014. Note how all of the spokes at or above horizontal
have now collapsed.
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Invincible Mine Complex Heritage Assessment
Figure 28
Looking in to the Invincible water
wheel wheelpit in 2014, where the
lower section of the wheel remains
partly intact.
The surviving water wheel fabric
allows some measurements and
observations to be made. The wheel
was 24 feet 2 inches in diameter and 4
feet 9 inches wide (7.3m diameter,
1.4m wide), and had timber spokes,
shroud, sole and buckets.2 The spokes
were internally braced with both
diagonal cross-braces and straight
braces. Timber sample were taken in
1995 and identified by Rod Wallace
(University of Auckland), who found
that the spokes were beech (Nothofagus
sp.) and the sole was totara
(Podocarpus hallii).
The wheel was a fairly robust timber structure of simple conventional design. Apart from the
hub, ring gear and fittings it was constructed from local materials (beech, totara and schist).
Its relatively simple design and construction did not allow for more advanced design features
such as curved and ventilated buckets that were seen on contemportary iron and part-iron
wheels (Petchey 1996).
Summary of Invincible Battery
The remains of the Invincible Battery suggest that it was conventional, with a timber kneeframe structure and key-mounted cams, powered by a wooden overshot water wheel. The
processing technology used initially was similarly conventional. The contemporary Mines
Inspectors’ reports state that blanket tables were used for gold saving, without the use of
amalgamating tables or mercury traps, and that a very high pyrites content in the ore meant
that a lot of gold was lost. The buddle on the valley floor and the bank of seven Berdans at the
battery site show how efforts were made to recover this lost gold. The period that this work
was being carried out was one of rapid change in gold processing technology, when the
introduction of the cyanide process would revolutionise the industry. The Berdans and buddle
illustrate the immediately pre-cyanide approaches to improving gold recovery. Cyanide
treatment was later tried at the Invincible mine, as was the addition of mercury to the mortar
boxes, but the combination of high pyrites content and the ultimate loss of the reef meant that
the mine failed.
2
Shroud=the sides of the rim. Sole=the inside lining of the rim. Bucket=the board that held the water,
mounted between the shrouds and against the sole.
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Invincible Mine Complex Heritage Assessment
Invincible Settlement
The Invincible settlement has not been the subject of an archaeological survey or any detailed
research other than Sutherland’s 1973 essay, and he estimated that 20 to 30 huts were present
in the settlement. Smith (1990) also mentioned that dwelling remains were to be found around
the mine and near Invincible Creek, and several of these are easily visible from the walking
track (Figures 29 & 30). From these observations together with comparisons with other hardrock mine site settlements, it is known that numerous hut sites are scattered around the
general area, each likely to consist of a level terrace and the remains of a schist
fireplace/chimney. The mine manager’s house location is known from historic maps (Figure 6
above), but this has yet to be identified on the ground.
Figure 29
A stone chimney ruin surrounded by regrowth trees just below the Invincible track near
where it enters the historic reserve in 2014.
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Invincible Mine Complex Heritage Assessment
Figure 30
Stone wall from a hut or other building on the Invincible terrace.
Invincible Mine Road & Huts
The track up to the Invincible battery site zig-zags up the mountainside from the valley floor.
This track would have been cut in about 1881 in order to transport the heavy battery and
mining machinery up to the battery and mine sites. According to Sutherland (1973: 6) the
track was recut using a bulldozer in more recent years, but the road line is probably all the
original 1880s route. The road is benched into the hillside for most of its length (Figure 31),
apart from a few areas where it passes through shallow cuttings (Figure 32). In general the
road is approximately 8 feet (2.4m) wide.
The road passes several hut sites as it climbs the mountainside. Near the start of the road there
is a derelict stone hut with a sheet iron chimney and collapsed roof (Figure 33). The roof and
chimney structure appear to be much younger than the stonework, and suggest that the ruin
was refurbished for use, possibly in the 1950s or 1960s. It is probable that the original ruin
was that of John McDougall’s store and post office.
Half way up the mountainside the track passes the remains of a log hut (Figures 34 and 35).
This was constructed in the (almost cliched) American style of stacked notched interlocked
natural logs, and measured 15 feet by 14 feet (4.6m by 4.3m). It was roofed with sheets of
white enamelled iron, covered with tarred material. The hut was possibly built in the 1930s
(Smith 1990), while the scattered artefactual material (which includes a 2 ! lb milk powder
tin and rubber insulated electrical wire) suggests a 1950s or 1960s last period of occupation.
The hut certainly post-dates the 1880s period of the Invincible Mine operation. There is
another terrace below the hut terrace, and nearby is the remains of the long-drop latrine that
had a square enamelled iron seat.
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Invincible Mine Complex Heritage Assessment
Figure 31
The Invincible track on a benched cutting as it climbs through regenerating scrub on
the lower slopes of the Richardson Mountains in 2014.
Figure 32
The upper section of the Invincible track
as it passes through an 8 feet wide cutting
in beech forest in 2014.
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Invincible Mine Complex Heritage Assessment
Figure 33
The stone ruin at the bottom of the Invincible track in 2014. This was probably
originally the store and post office associated with the Invincible settlement.
Figure 34
The collapsed remains of the log hut in 2014, beside the Invincible track. This hut was
possibly associated with Watherston’s workings.
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Invincible Mine Complex Heritage Assessment
Figure 35
Detail of the most intact corner of the log hut in 2014, showing its construction method
with notched and interlocked logs, together with a pile of the enamelled iron sheets that
were used for the roof.
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Invincible Mine Complex Heritage Assessment
Otago Pyrite Saving Company’s Works (Buddle)
The site of the Otago Pyrite Saving Company’s works is on the valley floor beside the
modern Rees Valley Road. The site is signposted. The most visible feature of the site is the
convex table (also known as a ‘buddle’ or ‘concentrator,’ and often mistakenly called a
‘Cornish buddle’), but there are also numerous other archaeological features in the vicinity
including a large pond or reservoir and a stone ruin.
The rotating convex table (Figure 36) was variously described as being 24 feet or 26 feet in
diameter, and was driven by a 10 inch diameter “Little Giant” turbine (AJHR 1886 C4: 22;
Otago Witness, 27 August 1886: 12). The top was measured during the 2014 site visit, and is
26 feet 6 inches across. The cement surface that was relaid in the 1980s is still in reasonable
condition, although moss growth and moisture retention due to leaf mould build up have
begun to make the surface deteriorate. In the centre of the table is a cast iron pylon (Figure
38) that once supported the arms (sweeps) that fed water onto the table. The sands were fed
into the distributing gutter at the table’s high point, and washed down by the flow of water.
Around the periphery of the table, and located under its ‘drip nose,’ is an iron gutter mounted
on a series of jockey wheel that run on a circular rail (Figure 37). This revolving gutter was
divided into four compartments, which passed the sand received off the table into the concrete
gutters around the table (Otago Witness 27 August 1886: 12). These three cement channels
are each six inches (150mm) wide (Figure 40), and are showing some deterioration (Figure
41). A cast iron arm that was once mounted radially to the table is lying on the ground (it was
still mounted when recorded in 1995).
Looking down the centre of the table, past the pylon mount, it is possible to see some of the
sub-surface concrete structure that lies beneath the table (Figure 39), and which gives a hint
of how much sub-surface evidence must exist at the site.
Figure 36
The Otago Pyrites Saving Company’s circular convex table in 2014.
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Invincible Mine Complex Heritage Assessment
Figure 37
The iron track and jockey wheels that support the revolving iron gutter under the ‘drip
nose’ of the table.
Figure 38
The central pylon on the buddle in
2014.
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Invincible Mine Complex Heritage Assessment
Figure 39
A view down the opening below the central pylon of the buddle in 2014. This hints at the
scale of the sub-surface pipework and infrastructure that probably exists at the Otago
Pyrites Saving Company’s site.
Figure 40
The series of 6 inch wide concentric
cement channels around the
periphery of the buddle in 2014.
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Invincible Mine Complex Heritage Assessment
Figure 41
Deterioration of the cement channels in 2014, showing a section that has broken away
exposing the reinforcing bars.
Figure 42
The cast iron arm that used to be mounted beside the buddle, in 2014. It was in place
when the site was visited in 1995.
Twelve metres to the west of the convex table is a large shallow pond or reservoir (Figure
43). This reservoir is dug into the slope on its east side, and has a stone and earth
embankment on its west and north sides. It is rectangular, measuring approximately 87 feet by
31 feet (26.5m by 9.5m), but with a bank projecting into the middle from the east side, and a
‘tail’ off its north end.
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Invincible Mine Complex Heritage Assessment
Figure 43
The large pond on the Otago Pyrites Saving Company’s site in 2014.
Beside the track in to the convex table from the road is a small stone ruin. It appears to be a
stone ramp and a rectangular structure (Figure 44), but it would require closer investigation to
confidently identify its function. Other features are scattered about the site, but once again no
systematic archaeological survey has been carried out. Peter Chandler (1984: 28) thought that
there was evidence that a cyanide plant had been used there as well, but it is not clear exactly
what features he was referring to.
Figure 44
The stone ruin beside the entrance to the Otago Pyrites Saving Company’s site in 2014.
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Invincible Mine Complex Heritage Assessment
The above section describes the Invincible Mine complex of sites as they are currently
understood. However, this site requires a thorough archaeological survey to be fully
understood. In particular the settlement sites around the mine and battery, and the Otago
Pyrites Saving Company’s site are not fully recorded. Not only does this mean that the full
extent of the site can not be determined, but also that there is no base line data to identify
deterioration or change in the sites, other than photographs such as those included here in
Section 10.
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Invincible Mine Complex Heritage Assessment
5.0
Cultural Connections
The cultural significance of a place is not a static and easily defined concept, and can mean
different things to different people. Cultural significance of a place can be considered with
regard to one or more specific cultural groups, and/or with regard to its importance to the
wider present population. A very good recent example of this is the management of the
Christchurch Cathedral in the wake of the Canterbury earthquakes; the wider community has
expressed considerable interest in the building as a cultural symbol of the city, resulting in
enormous resistance to the Anglican Church’s decision to deconstruct the building. The
building has strong and variable meaning to different groups. The Invincible Mine complex
can be regarded in a number of ways: as an historic technological site; as an historic site
where people lived and worked; as a modern walkway and cultural heritage visitor attraction;
and as a modern walkway that provides access to alpine scenery. Each of these attributes is of
interest to different groups today.
The Invincible Mine complex can historically be associated with a number of identifiable
people, groups and places. Nineteenth century gold mining was an international industry at all
levels of its operation. International finance (especially after the 1880s), technology (in the
form of both designs and actual items of machinery) and people all moved around the world’s
main goldfields (Petchey 2013: 302-314). The Invincible Mine is not unusual in that a
number of these international influences can be identified from both historical and
archaeological sources. The origins of the technology and equipment used in both the
Invincible Battery and Otago Pyrites Saving Company’s plant are discussed in detail in
Section 6.0 Contextural Analysis below. Here it is sufficient to note that this equipment can
be traced to numerous sources, including Australia, New Zealand, Germany and the USA (the
latter as a source of design rather than actual manufacture). One word of caution does need to
be made regarding the Otago Pyrites Saving Company’s convex table: this has often been
referred to as a ‘Cornish buddle’ (eg Smith 1990; Sutherland 1973), but as described above it
was actually manufactured in Germany.
The people involved with the mine complex are harder to associate with particular origins. As
is common with most such sites, the records often provide the names of the shareholders,
managers and engineers, but no information is provided about the ‘sixteen men employed
underground and eight men on the surface’ (in the 1885-86 year) (AJHR 1886 C4: 22). For
modern researchers it is often the lives of these workers that is of the greatest interest, as
illustrated by the Caversham Project in Dunedin (www.caversham.otago.ac.nz). Some of the
people that can be identified include the mine manager, Alfred Morrisby, the
storekeeper/postmaster John McDougall, the proprietor of the Otago Pyrite Saving Company
George Watson and the successive managers of the company’s works J.B. Neal and W.
Dickenson. Watson was a Scotsman who lived in Dunedin and was also involved with
scheelite mining nearby at Glenorchy (Bradshaw 1997: 15), and a detailed account in the
Otago Witness (27 August 1886: 12) described how Dickenson had been trained as an ore
dresser at Mount Bischoff in Tasmania. A number of influential mining experts are also
known to have visited the site, including Professor J.G. Black of the Otago School of Mines
(a Scottish immigrant) and the American expert on stamp milling T.A. Rickard. Rickard’s
report on the Invincible (Rickard 1898: 191) forms part of his classic text on stamper batteries
‘The Stamp Milling of Gold Ores’ that had an international audience. The available evidence
therefore indicates a strong cosmopolitan presence at the Invincible Mine complex.
New Zealand has a history of planned and unplanned, successful and failed settlements, and
each of these has a role in the history of the development of today’s society. McGill (1980)
listed 227 ‘ghost towns’ in his work Ghost Towns of New Zealand, and while this is by no
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Invincible Mine Complex Heritage Assessment
means a complete survey, it does give a good idea of how many settlements have failed for
one reason or another. Gold mining settlements were particularly prone to abandonment as
most only existed to serve a single economic activity. Recent work in Australia by Geraldine
Mate (Mate 2010) has focused on social meaning and constructs in the archaeological
landscape of an abandoned mining settlement, and sites such as the Invincible (Rees Gorge)
settlement that were briefly settled and then abandoned (meaning that the archaeological
record is not complicated by subsequent activity) have potential for similar future research.
Sutherland (1973) did some work on the Rees Gorge settlement and estimated that some 20 to
30 huts existed there, and there is much scope for further archaeological research.
The Invincible complex also has significance to modern populations. The reserve and track
easement were created in 1978, and so there is now a 36 year history of free public access to
the sites, and they are regularly visited by local and overseas visitors. During the 2014 site
visit (on a non-holiday weekday) a van of four Chinese tourists and a single New Zealand
visitor were all encountered at the buddle. Despite the apparent remote nature of the site, it is
only a little more than an hours drive from Queenstown, and about 20 minutes drive from
Glenorchy. The success of Peter Jackson’s Lord of the Rings and Hobbit films has brought
many visitors to the area either specifically seeking film locations or more generally enjoying
the mountain scenery, and the Invincible track provides a relatively easy route up the
mountainside to some spectacular viewpoints. Smith (1990: 234) noted the same values
(‘walking, exploring and appreciation of cultural heritage’) in the Otago Goldfield Park draft
management strategy (minus the Peter Jackson observations), and since she was writing the
Queenstown-Glenorchy road has been sealed, making visits to this area much easier than
previously.
There is an ongoing interest in local gold mining history, both amongst the general public,
and amongst local businesses that see the promotional attractions of such interest: for
example Arrowtown promotes itself as a gold rush village (www.arrowtown.com), and the
Goldfields Jet runs on the kawarau River (www.goldfieldsjet.co.nz). The Central otago
goldrushes of 1861 (Gabriels Gully) and 1862 (Dunstan) were the most influential events in
the settlement of the area, and the network of modern roads and settlement largely evolved as
a result of mining activity. The creation of the Otago Goldfields Park in the 1970s recognised
the importance of a number of widely scattered goldfields historic sites, and incorporated
them into a multi-site network of reserve areas linked by their themes and
management/interpretation material (Mason 1981). The Park concept still exists, now under
the Department of Conservation’s management. The Invincible Mine complex is part of the
Park, and was included for its evidence of mining techniques. At one time four-wheel-drive
tours ran trips up to the Invincible battery site, but these were stopped because of the damage
to the track (Smith 1990: 234). It is highly unlikely that such vehicle tours will ever be
restarted, which has the advantage of making the track a more pleasant walking experience,
and improves the experience of exploration for the visitor who does make it to the battery
site.
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Invincible Mine Complex Heritage Assessment
6.0
Contextual Analysis
The Invincible Mine and Battery and the Otago Pyrites Saving Company’s works were both
elements of the late nineteenth century international hard rock gold mining industry that had
its ultimate technological roots in the ancient world, but its immediate progenitor in the
aftermath of the Californian gold rush of 1848-1850, when miners began to seek reef gold
rather than just the easily-worked placer deposits. The series of Pacific Rim goldrushes
(California 1849; Victoria 1851; Otago 1861) followed by the discovery of the South African
Witwatersrand field (1885) saw not only the spread of mining activity around the world, but
also the concomitant development and spread of mining technology (Morrell 1968; Petchey
2013). Traditional centres of mining technology in Germany and Cornwall were joined by
other areas of innovation including California (the stamp mill), Glasgow (the cyanide
process) and South Africa (very heavy stamp weights and large mills) (Del Mar 1912; Morrell
1968; Salmon 1963). Mining equipment and technological expertise travelled around the
world either physically (as machinery exports) or as information (carried by individuals,
mining journals, text books and the establishment of Schools of Mines). New Zealand
benefitted from these developments, and the New Zealand mining industry was an active
participant in the international mining industry (Petchey 2013: 318).
The first hard rock mine in Otago was the Shetland Reef at Waipori, where a 4 stamp battery
was in operation by January 1863 (OPC V&P Session XVII 1863: 16). Subsequently many
other hard rock mines were set up in the province (and in the other goldfields throughout the
country), which used equipment sourced from Australia, America, Britain and New Zealand
(Petchey 2013). The 1870s to 1900s were the period with the largest number of operating
stamp mills in New Zealand (Petchey 2013: 154-155). The application of improving
technology (such as the cyanide process) was necessary to keep the industry viable, and many
mining companies failed despite possesing rich ore bodies because of the high loss of gold in
their tailings. The Invincible Mine fits in to this general narrative of the development of hard
rock gold mining in New Zealand very well, as it was discovered in the late 1870s, developed
in the 1880s, initially used conventional crushing and gold recovery processes, and then had
improved technology applied to address the loss of gold in the tailings. Finally, in common
with all other mines, the gold ran out and the mine was abandoned. The involvement of a
second company to reprocess the tailings was unusual but not unknown; the Ohinemuri River
Syndicate dredged the Ohinemuri River from 1897 until 1903 to process tailings from
stamper batteries upstream at Waihi (Ritchie 1990: 265a).
The Invincible Mine complex can be considered within several different contexts, including
the international origins of the mining/processing technology and equipment (including both
the origins of the designs and the actual place of manufacture), and the place of the mine
within the history and archaeology of the New Zealand mining industry. The technology at
the complex can be split into a number of discrete functional units: the mine; the water wheel;
the stamp mill; the Berdans; the convex table (buddle). These units are used as the basis of the
discussion below.
The mining technology is difficult to assess from an archaeological perspective as all of the
underground workings have collapsed (even the Machine Level stands for only a few feet).
Annual Mines Department reports (in the Appendices to the Journals of the House of
Representatives) confirm that normal mining practices were used, whereby horizontal drives
were put in, and the ore was then stoped out. The quartz was reported as being very loose in
nature, and the ground required a great deal of timbering (AJHR 1886 C4: 22), which means
that the workings would have quickly collapsed once the mine was abandoned. The size of
the mullock heaps indicates that the underground workings were reasonably extensive, and
the placing of these heaps indicates that there were at least five main drives. Photographic
evidence (see Figure 7) and the presence of tramway formations confirm that typical
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Invincible Mine Complex Heritage Assessment
nineteenth century narrow gauge mine tramways were employed underground and on the
surface to the battery and tipheads. No vertical shafts or winding gear were employed, as the
mountainous nature of the county meant that all mining and ore handling could be carried out
using gravity (ie, drives and overhead stopes, and a downhill run to the battery). The
Invincible Mine can therefore be compared to other alpine mining operations where the main
workings were above the processing plant and no winding gear or shafts were employed, such
as the Macetown mines (including the Homeward Bound, Premier/Maryborough and Sunrise
mines) (Petchey 2002).
The water wheel was a good example of a wooden overshot wheel of the period.
Photographic evidence indicates that many wooden wheels were in use in New Zealand mines
(and other industries), some of them very large. A good example was the 50 feet diameter
Wealth of Nations wheel near Reefton (Smith 2001: 87; Thornton 1982: 63). However,
wooden wheels decay, and it is only the large part-iron water wheels that have survived in
reasonable condition, due to the robust nature of their cast- and sheet-iron rims. The best
Otago examples are the Young Australian and Serpentine wheels (Figure 45) (Petchey 1996;
Thornton 1982: 63). Despite is poor condition, it is possible to make a number of
observations about the design of the Invincible water wheel. It was a very conventional
simple wheel in many respects, with timber used for most of its construction. The buckets
were formed by simple flat timber boards, at a time when curved iron buckets (which gave
better water flow in and out) were commonplace. However, the wheel did utilise ring-gear
drive, where the drive was taken by a spur gear running against a large iron ring gear mounted
on the side of the wheel. This allowed wheels so fitted to be more lightly built than those that
took the drive out through the wheel shaft. This design feature was the most common
‘advanced’ feature recorded in surviving water wheel in Otago (Petchey 1996: 65). Overall
the Invincible water wheel was a typical wheel of the period, built of local materials, and
serviceable and adequate but not particularly advanced. Given the availability of ample water
at sufficient elevation to drive an overshot wheel nearby in Invincible Creek, there was
probably no need to invest a great deal of money in an advanced wheel when a simpler one
was sufficient and cheap to run.
Figure 45
The Serpentine water wheel and battery (site H42/2). This wheel has been restored by
the Department of Conservation.
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Invincible Mine Complex Heritage Assessment
The stamp mill was a conventional ten-stamp machine, probably built by Thompson & Co. of
Castlemaine in Australia (Otago Witness 17 May 1884: 12; 14 June 1884: 9). The stamps and
mortar boxes were removed after the battery closed, so it is not possible to assess their design,
but the camshaft is of conventional design appropriate for the reported stamp weight (8 cwt)
and date of manufacture, and the cams are mounted in the most common drop order found in
New Zealand mills (Petchey 2013: 225). The timber trestle frame is also typical for midweight mills of the period (Petchey 2014: 5). The best surviving example of this general
frame form is probably the Canton Battery (site H44/831) at Waipori in Otago (Figure 46).
The mill therefore appears to be a conventional machine of the period, typical of many that
were built in Australia and New Zealand.
Figure 46
The Canton Battery at Waipori (site H44/831).
An example of a trestle-framed stamp mill.
The row of seven Berdans is more unusual. The Berdan grinding pan was developed in the
USA by Hiram Berdan in the 1850s, and was widely adopted in New Zealand for the further
grinding and amalgamation of tailings and concentrates (Berdan 1853; Petchey 2013: 130).
Although H.A. Gordon (1906: 415) was dismissive of the design, the Berdans at the
Invincible Battery do appear to have been very effective as they substantially reduced the
gold loss through the tailings. They were manufactured by Kincaid McQueen & Co. of
Dunedin, and are conventional in design other than their use of bottom-drive (top-drive is
more common amongst surviving examples). The set of seven Invincible Berdans are the
largest set to survive in New Zealand, the closest comparable group being the six Berdans at
the Luck at Last Reduction Works (site T12/601) near Whangamata (Figure 47). However,
these Berdans are no longer mounted, and have been removed from their site and then
returned, so lack the intactness of the Invincible examples. The Taitapu Battery (site M25/86)
in NW Nelson has four Berdans, still in association with the 20 stamp mill (although all of the
timber framing is gone) (Petchey 2013: 458-462).
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Invincible Mine Complex Heritage Assessment
Figure 47
The row of six Berdans at the Luck at Last Reduction Works (site T12/601).
Buddles relied on the high specific gravity of gold and concentrates containing gold to
separate these from the barren tailings. Round buddles were circular tables that sloped either
in or out, and the finely crushed pulp was fed in at the high point and washed down with a
flow of water. The heaviest material would settle out first, and the lightest material would be
carried away and discarded. Buddles were used in a number of New Zealand mills, such as
the Woodstock at Karangahake (Auckland Star, 20 April 1895: 5) and McGill’s Battery at
Macraes (Otago Witness, 23 September 1903: 23). The Otago Pyrites Saving Company’s
circular convex table is the only known surviving example in New Zealand, and it is not
known whether any of the other buddles were similar in design. Davey (1996) has reported
that the Museum of Victoria has German models of buddles, and thought that these may have
been how the design was introduced to Australia. Certainly it is known that the Invincible
buddle was of German manufacture, was probably influenced by the Mount Bischoff tin
mining operation in Australia, and the concentrates were shipped to the Sandhurst Pyrites
Works in Victoria for smelting (Otago Witness 2 January 1886: 14; 27 August 1886: 12). The
common misconception that it is a ‘Cornish buddle’ has already been discussed above.
The Invincible Mine complex is therefore a very good representative example of a nineteenth
century hard rock gold mining operation, and in particular of the alpine mines found in the
Queenstown Lakes area. This context within the wider Otago goldfields has also been
mentioned above in Section 5.0 Cultural Connections, in relation to the site’s inclusion in
the Otago Goldfields Park. The mining and processing technology at the Invincible Mine
complex is in many ways typical of contemporary mines in New Zealand, Australia and
America, with the water wheel, stamp mill and Berdans all being good representative
examples, albeit quite decayed in the case of the wheel and mill. However, the set of seven
Berdans is the largest surviving set in New Zealand, and represents how existing technology
was adopted at a scale to suit the problem: where normally one or two Berdans would be used
to treat concentrates, at the Invincible the loss of gold was so great a large number of Berdans
was installed to be able to considerably increase the quantity of tailings that could be
processed. The other method employed to recover the lost gold from the Invincible Mine, the
Otago Pyrites Saving Company’s buddle on the valley floor, is the only known example in
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New Zealand, and is unusual in that it represents the direct importation of German equipment
to New Zealand. Most goldfields machinery was sourced from Britain, Australia, the USA or
locally manufactured, despite the fact that Germany was a long-established centre of mining
technology. This underlines the international nature of the late nineteenth century mining
industry, where although the main linkages were with the Empire and English speaking
world, other associations with centres of mining expertise were also maintained.
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7.0
Assessment of Significance
Most historic places in New Zealand are assessed using a recognised heritage values system.
DOC uses the significance assessment criteria contained within the Historic Places Act 1993
(recently replaced by the Heritage New Zealand Pouhere Taonga Act 2014). Heritage New
Zealand (previously the New Zealand Historic Places Trust) is the national authority in the
assessment of the significance of historic places. The current Heritage New Zealand
assessment criteria are used in its List (previously the NZHPT Register) proposal guidelines
(www.heritage.org.nz/the-list/-/media/8c1c89c0ef5d48a19821975d1eef68de.ashx).
These
criteria are:
Historical, cultural, aesthetic, archaeological, architectural, scientific, social, spiritual,
technological and traditional significance or value.
Section 66 (3) of the Heritage New Zealand Pouhere Taonga Act 2014 further describes these
criteria for heritage sites to be included in the New Zealand Heritage List. For the purposes of
this report these criteria have been amalgamated under three headings: Historical (historical,
social); Physical (archaeological, architectural, scientific, technological); and Cultural
(aesthetic, spiritual, traditional).
The Invincible Battery and Otago Pyrites Saving Company’s buddle have long been
recognised as significant sites, most notably by their inclusion in the Otago Goldfields
Heritage Park and by their NZHPT registrations (now Heritage New Zealand ‘listings’). Both
the Department of Lands & Survey and the New Zealand Historic Places Trust therefore
carried out significance assessments, and values raised in these assessments are included in
the discussions below.
7.1 Historic Significance
Gold mining was one of New Zealand’s most important industries in the late nineteenth
century, and for much of the decade until 1871 gold exports constituted more than half of
New Zealand’s export value (Salmon 1963: 209). The infrastructure and settlement pattern of
the main gold mining districts (Otago, West Coast, Thames/Coromandel) were established
during and in the aftermath of the various gold rushes. Towns such as Lawrence, Alexandra,
Clyde and Arrowtown were all established during this period, and survived because they
became service centres for local farming and other activities that replaced the mining
industry. Other settlements, such as Bendigo, Logantown, Macetown, Bullendale and Rees
Gorge existed to serve only mining (in some cases just a single mine), and disappeared once
mining ceased. The gold discoveries created an economic boom that made Dunedin the
commercial centre of New Zealand for many years. Gold mining is therefore a central aspect
of Otago’s historical development.
The Invincible Mine complex is associated with the peak years of hard rock goldmining in
Otago and New Zealand in the 1880s and 1890s, when the mining industry was a major
employer and exporter, and production was being maintained by international technological
advances and capital investment (Petchey 2013: 59). The Invincible Mine was an example of
a smaller operation that was locally financed, and which focussed on relatively shallow and
easily accesible gold deposits. This contrasts with some of the large and deep mines that were
developed with overseas (particularly British) capital, such as around Karangahake (near
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Waihi) and Reefton. The importance of improved technology was proven at the Invincible
when the Otago Pyrites Saving Company installed their works to re-process the tailings that
still contained much gold due to the pyritic nature of the ore. The works was novel and
advanced enough to be the subject of an extremely detailed account published in the Otago
Witness (27 August 1886: 12). The Invincible Company responded to this success by
installing the less novel, but in practice just as effective, set of Berdans that still exists.
The Invincible Mine complex is therefore a good representative example of a moderate size
late nineteenth century hard rock gold mine which was in many ways conventional, but which
also displays interesting technological responses to the problem of refractory ore. It therefore
fulfils a number of the Section 66 (3) criteria, including (a) the extent to which the place
reflects important or representative aspects of New Zealand History, and (g) the technical
accomplishment, value, or design of the place.
The Invincible complex is therefore locally and regionally significant as a representative
example of an historical hard rock mine, and nationally significant as an example of the use
of international technology in an attempt to address problems with refractory ore.
7.2
ysical Significance
The physical significance of the Invincible Mine complex rests in its overall intact nature, and
the presence within this complete system of the set of seven linked Berdans, and the
buddle/concentrator. In 1990 Smith (p 233) stated:
‘What is important about the Invincible Mine and Concentrator is that the whole
system, including the source of ore, the energy source, various methods of processing
and the associated infrastructure of dwellings and roads, is intact, and the extant remains
are in a relatively compact area.’
This statement still holds true. The complete system, although ruinous, is present and
(archaeologically) intact and unmodified, within an unmodified landscape setting. The visible
evidence of the mining and processing system can be appreciated by the casual visitor or
studied by the researcher, and the overall site also contains a great deal of sub-surface
archaeological evidence that has potential for future investigation.
The site meets a number of the Section 66 (3) criteria particularly (c) the potential of the place
to provide knowledge of New Zealand History, (g) the technical accomplishment of the place
and (k) the extent to which the place forms part of a wider historical and cultural area.
The archaeological potential of the complex is very high. The settlement has the potential to
provide information about the lives of workers and their families in a remote and
mountainous setting, while the battery and concentrator works have the potential to provide
information about the technology employed. The concentrator works site on the valley floor
would be particularly informative, as no similar site has ever been investigated in New
Zealand.
The set of seven Berdans is not technologically unique, as Berdans were widely used in New
Zealand and many survive, but it is the largest set in the country, and they are intact, in situ
and in good condition with their drive train in place. The original timber was replaced in
2001, and so the framework is now a replica but this does not detract from their significance.
The rotating convex table/concentrator/buddle is unique in the New Zealand goldfields, as no
other examples are known. It is also in situ, and both surface (visible) and sub-surface
archaeological evidence of the Otago Pyrites Saving Company’s works survives, but has yet
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to be investigated or even recorded in any detail. The table is not only a unique item, it is also
a rare example of equipment that was imported from Germany, which was an important
centre of mining tecchnology but not well represented in the Anglo-world orientated New
Zealand goldfields.
The Invincible Mine is an element of the Otago and wider New Zealand goldfields, and its
inclusion in the Otago Goldfields Park in 1978 not only recognised its individual significance,
but also importantly recognised that the concept of the historical goldfields could be applied
to discrete sites over a very wide area. This acknowledgement is important as it recognises
that an historical or cultural area does not necessarily have to be contiguous.
The Invincible Mine complex is therefore regionally significant as a good representative
example of a moderate sized alpine gold mining system, and nationally significant when the
unique buddle/concentrator is taken into account within this intact system. All aspects of this
system would repay further archaeological investigation. It must be emphasised that the
physical significance of the buddle is high because it is in context with the rest of the overall
site, and the entire Otago Pyrites Saving Company works site is part of this significant site,
not just the buddle itself.
7.3 Cultural Significance
The cultural significance of the Invincible Mine complex is also high, although less than its
historical and physical significance. The cosmopolitan nature of both the technology and the
people involved with goldfields enterprises such as this were an important element in the
development of modern New Zealand society. The goldfields were a mixing pot of people
and ideas, and the infrastructure and settlement pattern of the modern landscape was largely
formed during the gold mining period. The Invincible Mine complex is part of this wider
historical/archaeological/social landscape. The archaeological potential of the settlement site
in particular also has the potential to provide information about the lives of the people who
lived in this remote place in the 1880s.
In the modern world the Invincible Mine represents both the opportunity to explore aspects of
this history (for both the serious researcher and the casually interested visitor), and the
opportunity to walk in an alpine environment with spectacular views. As a Reserve with free
and unfettered public access it is part of a tradition of access to the back country that New
Zealanders have always enjoyed, and is an important aspect of New Zealand culture.
The Invincible Mine complex is therefore locally and regionally moderately significant as
both an example of the cosmopolitan goldfields population/technology, and as a modern
visitor destination that shares both cultural heritage and scenic alpine values.
8.0
Comparative Analysis
The Invincible Mine complex is part of the New Zealand goldfields archaeological landscape,
which stretches from Fiordland north to Great Barrier Island, and can be compared to a
number of other hard rock gold mine sites around the country. The most directly comparable
sites are the other Central Otago/Lakes District alpine sites, such as Bullendale and
Macetown, although both of these are actually clusters of mines rather than a single unit.
Other goldfields have simlar mountainous settings, and the Britannia (site L29/15) and
Croesus (site L29/2) mines on the West Coast, and Kirikiri (site T12/1410) and Bendigo (site
T13/90) in the North Island, are comparable, as they were moderately sized mines with 5 or
10 stamp mills. One of the features of many of these mountainous sites is that the reef
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systems were accessible by driving and stoping, and shafts and winding gear were not
required as all of the rock (mullock and ore) could be handled using gravity. The Invincible
mine is a good example of a gravity fed system as the mullock heaps of the upper workings
are visible from the battery site on the mountainside above, while the buddle/concentrator is
on the valley floor far below. The Homeward Bound Mine (site F41/477) at Macetown gives
a similar experience, as the battery is intact (with a Berdan and parts of a Wilfley table), and
the pylons for a gravity aerial cableway still march up the mountainside to the mine workings
above. One feature of the Otago sites is that they are often in open tussock country, and are
relatively easy to see. Central Otago also has the best preservation of timber battery structures
in the country due to its arid climate. Most West Coast, Nelson and Thames/Coromandel sites
are in forest, and inspection is difficult, and in these damper conditions timber elements tend
to decay more quickly. In addition, the North Island sites have a relatively poor survival rate
of machinery when compared to the South Island, probably largely due to their ease of access
and proximity to population centres and scrap dealers (Petchey 2013).
In terms of the technology used at the Invincible Mine complex, the discussions above have
identified the set of seven Berdans and the rotating convex table/buddle/concentrator as the
most significant elements in the system. Berdans are relatively common in New Zealand
mining sites, but usually exist as single or double examples. There are no comparable sets of
seven units, but one set of six Berdans (Luck at Last, site T12/601) and one set of four
Berdans (Taitapu, site M25/86) are recorded (Table 3). The Invincible Berdans are also in
relatively good condition, are still mounted (albeit now in a replica frame) with their drive
gearing intact, and are unusual (but not unique) examples that were driven from below (top
drive is most common).
Table 3
Surviving multiple Berdan installations in New Zealand
Site Name
Albion
Alpha
Battery Ck (Kirikiri)
Croesus
Golden Lead
Golden Site
Govt. Coromandel
Invincible
Johnston’s United
Kirwan’s Reward
Luck at Last
Taitapu
Welcome jack
Wellington
NZAA No.
Q27/112
B46/42
T12/1410
L29/2
L31/29
B46/88
T10/1115
E40/58
M25/73
L30/62
T12/601
M25/86
T11/693
O28/47
No. of Berdans
2
2
2
2
2 (1 taken to museum)
2
3
7
2
2
6
4
2
2
Drive
Top
Top
Top
Bottom
Top
Top
Top
Bottom
Top
Top
Top
Top
Top
Top
The Otago Pyrites Saving Company’s rotating convex table is unique in New Zealand, as no
other examples are known to survive. Historical sources record other buddles as having been
used in New Zealand (Auckland Star, 20 April 1895: 5; Otago Witness, 23 September 1903:
23), but there is no evidence as to how these compare with the Invincible example. In addition
to the rarity of the item, it is also an unusual example of German machinery in the goldfields.
The New Zealand mining industry was receptive to international developments in technology,
but most imported designs and equipment originated in the Anglo world of Britain, Australia
and the USA (Petchey 2013: 311-312). While Germany was a long-established centre of
mining expertise, its direct influence in New Zealand was relatively limited.
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The rest of the Invincible Battery equipment is conventional. The stamp mill is a mid-weight
ten stamp unit fitted to give the most commonly recorded drop order in New Zealand sites.
The timber trestle frame is of a general type that is known to have been used for a long
period, and is now in extremely poor condition. The water wheel was also a conventional
design, and the upper half of the wheel has now completely collapsed. No original all-timber
water wheels now survive in the goldfields (the small wheel at the Canton Mine (site
H44/831) at Waipori was the last to succumb), but several good examples of iron-rimmed
water wheels do exist including the Young Australian (site F42/28) and Serpentine (site
H42/2) wheels.
The Invincible Mine complex is therefore overall a very good representative example of a
moderate sized alpine hard rock mine of the late nineteenth century, typical of many that were
locally funded and which focused on relatively shallow gold deposits. What makes the
Invincible stand out from other similar mines are the seven Berdans and the Otago Pyrites
Saving Company’s processing site, which contains the best example of a circular buddle in
New Zealand. The Invincible Mine complex therefore represents a complete system, with
some elements that are highly represenative of similar sites, and other elements that are
unique. The significance of the place is as a complete system where all elements are in
context. Overall it is locally and regionally very significant, and the Otago Pyrites Saving
Company’s site is unique and nationally significant.
However, as stated above, a full detailed archaeological survey of the overall site has yet to be
undertaken, and this is likely to identify further features and add to the archaeological
significance of the site.
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9.0 Sources & reports
Appendices to the Journals of the House of Representatives. 1863-1938
Berdan, H. (1853) ‘Machine for Pulverizing Auriferous Quartz and Amalgamating the Gold.’
US Patent Office, Letters Patent No. 9741, dated May 24th 1853.
Bradshaw, J. (1997) Miners in the Clouds. A hundred years of scheelite mining at Glenorchy.
Lakes District Museum, Arrowtown.
Chandler, P.M. (1984) Head of Lake Wakatipu, Schools Centennial 1884-1984. Central Otago
News Ltd., Alexandra.
Davey, C.J. (1996) ‘The Origins of Victorian Mining Technology, 1851-1900.’ The Artefact,
19: 52-62.
Del Mar, A. (1912) Stamp Milling. A Treatise on Practical Stamp Milling and Stamp Mill
Construction. McGraw-Hill Book Company, New York.
Galvin, P. (ed) (1906) The New Zealand Mining Handbook 1906. Government Printer,
Wellington.
Gordon, H.A. (1906) Mining and Engineering; and Miners’ Guide. Government Printer,
Wellington.
McGill, D. (1980) Ghost Towns of New Zealand. Reed, Auckland.
Mason, B. (1981) Otago Goldfields Park. Landscape 10 (November 1981). Department of
Lands & Survey.
Morrell, W.P. (1968) The Gold Rushes. Adam & Charles Black, London (second edition, first
published 1940).
Otago Daily Times (Newspaper, Dunedin)
Otago Provincial Council, Votes & Proceedings. 1863
Otago Witness (Newspaper, Dunedin)
Petchey, P.G. (1995) ‘Conservation Plan, Invincible Mine, Invincible Concentrator,
Invincible Mine Historic Reserve.’ Report for Department of Conservation.
Petchey, P.G. (1996) ‘Otago Water Wheels. The Industrial Archaeology of Water Wheels in
Otago.’ MA thesis, Anthropology Department, University of Otago.
Petchey, P.G. (2002) Archaeological Survey of the Arrow River and Macetown, Otago.
Department of Conservation, Wellington.
Petchey, P.G. (2013) ‘The Archaeology of the New Zealand Stamp Mill.’ Phd Thesis,
Department of Anthropology and Archaeology, University of Otago.
Petchey, P.G. (2014) ‘The Archaeological Interpretation of the New Zealand Stamp Mill.’
Australasian Historical Archaeology, 32: 3-13.
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Queenstown Lakes District Council, District Plan.
Rickard, T.A. (1898) The Stamp Milling of Gold Ores (second edition). The Scientific
Publishing Co., New York.
Ritchie, N.A. (1990) A Survey of Historic Mining Sites in the Thames and Ohinemuri Areas of
the Hauraki Goldfield. Department of Conservation, Hamilton.
Salmon, J.H.M. (1963) A History of Goldmining in New Zealand. Government Printer,
Wellington.
Smith, N. (2001) Heritage of Industry. Reed Books, Auckland.
Smith, P.J.M. (1990) ‘Otago Goldfields Park, Management Strategy (Draft).’ Department of
Conservation.
Sutherland, A.G. (1973) ‘Rees Gorge Gold Mining Settlement.’ Essay in part requirement for
degree in historical geography, University of Otago.
Thornton, G.G. (1982) New Zealand’s Industrial Heritage. A.H. & A.W. Reed, Wellington.
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10.0 1995 Photos
Photographs of the Invincible Battery and Otago Pyrites Company Buddle taken in 1995 by
P. Petchey.
The overall battery site.
The water wheel, with one spoke still pointing to the sky.
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The water wheel hub.
The water wheel hub, and a view
down into the wheel pit where much
of the lower wheel structure was
intact.
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The water wheel (left) and collapsed stamp mill (right).
The collapsed stamp mill.
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The collapsed stamp mill, showing one set of five cams.
The row of seven Berdans.
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A detail of the Berdans.
A detail of the drive mechanism of the Berdans.
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The Otago Pyrites Saving Company’s circular convex table.
The central pylon on the buddle.
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A detail of the peripheral drains of the buddle.
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11.0 Other Data
Drawing of Berdans. Works Consultancy Services, 1989.
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Otago Witness article, August 27th 1886
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