Geological Survey
GEOLOGICAL SURVEY EXPLANATORY REPORT
from the Department of Mines Tasmania 1979
SHEFFIELD
Sheet 37
The Sheffield Quadrangle
There have been approximately thirty mines and prospects in the Moina and Mount Round districts, but only three mines have achieved significant production. These are the Shepherd and Murphy tin-tungsten-bismuth mine at Moina, the Round Hill silver-lead mine at Round Mount, and the Bell Mount alluvial goldfield. The reasons for such a high failure rate in an area which, at first glance, appears particularly rich in metallic minerals is best summarised by Reid (1919, p. 66), when he states “Those responsible for the early development of many of the mines have failed to appreciate the peculiar structure of the geological formations encountered here, consequently many mining companies have little to show for the heavy expenditure incurred. In some instances companies were formed for the purpose of carrying out operations on sections which were pegged in alignment with ore-bodies existing on neighbouring properties, on the supposition that the ore bodies would be continuous and pass into them. At the time of the gold-mining boom in this locality, metallurgical plants for the treatment of the ores were erected before they were warranted by developed ore reserves. Plants were erected even on the supposition that the gold content and the size of the veins would increase with depth; in other cases this procedure was followed for purely speculative purposes. This policy, naturally, has had a ruinous effect on the mining industry, the direct result being the abandonment of the fields before extensive developmental work had been carried out.”
The first report on mineral deposits in the Sheffield Quadrangle is by Thureau (1881), describing gold deposits south of the Minnow River, silver-lead deposits on Mount Roland and Mount Claude and in Claude Creek, and the Barrington copper deposits. The silver-lead deposits in Claude Creek are the subject of a later report by Thureau in 1885.
The first mention of mineral deposits to the west of the River Forth is in the report by Montgomery (1894), referring to the silver-lead deposits in Claude Creek and the tin-tungsten deposits at the Iris, Dalcouth and Shepherd and Murphy mines. Smith (1897) described the early workings of the Shepherd and Murphy mine, with further detailed descriptions of this mine being given by Smith in his report on the Bell Mount and Middlesex mineral fields (Smith, 1899), which also includes descriptions of the Claude Creek deposits.
Waller (1901) described the Shepherd and Murphy, Bell Mount and Iris mines, while the copper deposits in the vicinity of the Leven and Alma (Barrington) were described by Twelvetrees (1903, 1906). In a later report, Twelvetrees (1908) concluded that the Bell Mount mineral field (the Moina and Round Hill districts) on the whole would probably prove to be one with numerous small, but rich lodes.
The first major report on the mineral deposits in the Moina and Round Mount districts is by Twelvetrees (1913). Twelvetrees was the first to recognise the genetic relationships of these deposits to the Dalcouth granite and the zonation of metals around the granite. In his conclusions, Twelvetrees states that “the deposits of tin, wolfram and bismuth ores are in the pneumatolytic zone within the granite itself and the surrounding mantle of sediments, while auriferous silver-lead and zinc blends (sphalerite), with free gold released from them, are found in the outside zone at a greater distance from the magmatic reservoir” (Twelvetrees, 1913, p.130). Summary descriptions of the Shepherd and Murphy mine and the All Nations mine, and other mines in the vicinity are given by Hills (1916).
The next major report is by Reid (1919) who mentions that with the exception of such mines as the Shepherd and Murphy, All Nations, Squib and Round Hill, little additional development had taken place at most of the prospects since the early reports by Smith and Twelvetrees. Reid gives detailed descriptions of most of the deposits in the Moina and Round Mount districts, in particular the two major producers in the area, the Shepherd and Murphy and Round Hill mines.
Since Reid’s (1919) report there have been numerous reports on individual mines, in particular the silver-lead deposits in the vicinity of Round Mount (eg. Hughs, 1948; Jennings, 1958) and the tin-tungsten deposits in the Moina area (eg. Broadhurst, 1934; Keid, 1943; Nixon, 1954; Blake, 1956; Robinson, 1958; Williams, 1958).
Recently, the geology and mineral deposits in the Moina and Round Mount districts were investigated by Gee (1966), with summary descriptions given by Elliston (1953b) and Jennings (1965). The skarn deposits within the contact aureole of the Dalcouth Granite have been investigated in detail by Webb (1974) and are currently being evaluated by Comalco Limited (1979).
GOLD
Varying amounts of gold have been recovered from most of the mines in the Moina and Round Mount areas, but there are only two mines, Higgs and Devonport, from which gold was exclusively mined. The major alluvial workings were on the Bell Mount goldfields, 1.5 km north of Moina. Deposits of alluvium in the valleys of the River Forth (eg Cooper-Smiths) and Minnow River have also been prospected for gold.
The total gold production from the Sheffield Quadrangle is in excess of 175 kg, the main producers being the Higgs gold mine (28.35 kg), the Bell Mount goldfield (113.4 kg) and the Round Hill silver-lead mine (31.46 kg).
Higgs (Sunrise) [48/097911]
This mine is situated on the south bank of Narrawa Creek, approximately 2.5 km east of Moina. The deposit was reported on by Blake (1937b), Keid (1947) (referring to the Sunrise mine) and Jack (1961), from which the following description has been summarised.
Gold was first discovered in the area in 1893 but it was not until 1934 that mining began, continuing intermittently until 1947. Production during the period 1935-1941 was 18.96 kg of gold (Keid, 1947). Jack (1961) estimated that a total of 28.35 kg of gold had been recovered by underground mining and surface sluicing during the period 1893-1947. Since 1947 the mine has been abandoned.
Devonport [48/005919]
The Devonport gold mine is situated on the west bank of Devonport Creek, approximately 6 km west of Moina. In the first report on the mine, Twelvetrees (1913) described a discontinuous series of quartz and gossanous formations and suggested that the encouraging gold assays obtained in surface outcrops were the result of secondary enrichment and could not be expected at depth. Similar conclusions were later reached by Broadhurst (1934) and Henderson (1939). Collins (1975a) suggested the irregular nature of the quartz lenses was another major deterrent to mining.
Narrawa Reward [48/105913]
Situated on the north bank of Narrawa Creek, about nine metres above the creek. The workings were apparently abandoned well before Twelvetrees (1913) inspection.
Star of the West [48/315935]
Thureau (1881) records the discovery of alluvial gold in gravel on the banks of the Minnow River and in surface specimens from the slopes to the south of the Minnow River, near the Star of the West workings.
Bell Mount [48/075930]
The Bell Mount alluvial goldfield is situated approximately one kilometre south-west of Bell Mount in the headwaters of Bell Creek. Gold was discovered in the area in 1892 and the field was almost worked out within two years. Since then the field has received intermittent attention from prospectors. Twelvetrees (1913) estimated 113.4 kg of gold was recovered during the first two years. The main workings are in Bell Creek (Broadhurst, 1934). The gold occurs as flat nuggets commonly weighing 85 g, with the largest nugget weighing 624 g. The shape of the nuggets, flat and smooth on one side and rounded or bulbous on the other side, suggests the gold originally occupied joint planes or small veinlets in the host rock (Broadhurst, 1934).
Cooper - Smiths [49/235180]
Twelvetrees (1906) reported that alluvial gold had been recovered from alluvial flats near the Paloona Bridge, the confluence of the Forth and Wilmot Rivers.
SILVER - LEAD
Silver and lead have been mined in significant economic quantities in the quadrangle. Nearly all the silver and lead produced has come from mines in the Round Mount district and most of this from the Round Hill Main (or Eastern) workings during the period 1908-1927. Minor amounts of silver and lead have been produced from two other small silver-lead deposits (Wilmot, Prestons) and minor amounts of silver have been produced from some of the tin-tungsten and copper deposits.
ROUND MOUNT DISTRICT (after Jennings (1958))
The discovery of silver-lead deposits in the bed of Claude Creek north of Round Mount was made by two prospectors, Shepherd and Weeks, about 1878. Whilst early developments of these deposits did not immediately disclose any large rich ore bodies, they stimulated the search for further deposits in the vicinity. Within a few years of the original discovery further metalliferous deposits were discovered at the Round Hill Extended, Round Hill Western and Tin Spur workings, together with a number of other small prospects in the general area.
Development of these deposits proceeded sporadically for about the next 30 years. However, to date, the original deposits at Round Mount (the Round Hill workings) are the only ore bodies which have achieved any important production. The structure of the Round Mount lodes proved extremely puzzling to the early workers and although a great deal of prospecting was carried out much of this proved to be misguided.
Despite a number of set-backs, prospecting and development was pushed on and eventually a number of large high-grade ore bodies were located by driving south under Round Mount from the original lodes discovered in Claude Creek. The period 1913-1925 was the hey-day of the Round Hill Silver-Lead Company and some of the loads discovered were exceedingly rich.
The Round Hill Silver-Lead Company ceased operations in 1927, by which time the majority of the large ore bodies had been worked out. Even at this stage the structure of the ore bodies was still not clearly understood, and to a large extent this severely hampered the mining operations in the area. The West Claude Mining Syndicate took up the leases in 1948 and carried out further exploration work and erected a small mill which operated until 1951. Again, much of this work was misguided due to a non-appreciation of the structural problems involved and work ceased about 1954.
Wilmot (Washington) [48/075940]
This prospect, later known as the Washington silver-lead mine (Scott, 1927a), is situated on the east bank of the Wilmot River about two kilometres west of Bell Mount and one kilometre north-east of the Wilmot Dam. Irregular veinlets of galen and chalcopyrite within tubicolar sandstone and quartzite of the Moina Sandstone were discovered here in 1893 during the boom days of the Bell Mount goldfield.
Mount Claude prospect
To the north of Mount Claude, at Gilberts prospect [about 48/195912], Thureau (1881) described pyrite, siderite, calcite and galena occurring in veins of white quartz within Cambrian schist. These early discoveries led to further, but unsuccessful exploration in the area that is later referred to by Reid (1919) as the Mount Vandyke prospect.
TIN - TUNGSTEN - BISMUTH - MOLYBDENUM
All the tin -tungsten - bismuth - molybdenum deposits are located in the Moina and Round Mount areas, in the south-west corner of the quadrangle. The main producer was the Shepherd and Murphy mine at Moina, which operated intermittently between 1893 and 1957.
Dalcouth (Auldana) [48/106905]
Situated on the south flank of Dolcoath Hill, just below the summit, the mineralisation at the Dolcoath prospect was discovered in 1891 and is hailed as the first discovery of cassiterite and wolframite in the Moina district (Reid, 1919).
Sayers [48/114910]
A zone of mineralisation has been prospected on the steep north-east flank of Dolcoath Hill between Narrawa Creek and Lake Cethana. The numerous veins within the zone, collectively known as Sayers prospect, have been explored by a number of shallow shafts and short adits and numerous trenches.
Elliston (1953a) concluded that although the veins are numerous, they are of insufficient number to warrant exploitation.
Princess (Urquharts) [48/118910]
This prospect, referred to as Urquharts prospect by Twelvetrees (1913) is situated on the east flank of Dolcoath Hill.
Premier [48/123902]
Situated on the east side of Lake Cethana, numerous quartz veins occur near the eastern boundary of the Dolcoath Granite.
Hidden Treasure [48/123905
Discovered about 1890, the Hidden Treasure lodes are situated adjacent to the old Lorrina Road on the north-west tip of Tin Spur. Only the two main veins have been explored.
Squib (Gurrs) [48/100912]
Located on the north flank of Dolcoath Hill about 45 m above Narrawa Creek the Squib mine, referred to as Gurrs mine and Packetts workings by Twelvetrees (1913) occurs on the contact between the Dolcoath Granite and Moina Sandstone.
The principal developments at this mine have been on two levels 36 m apart (Reid, 1919). On the upper level, an open cut 7.6 m deep has been excavated. In the lower level, two sub-parallel veins diverge at a point 30.5 m from the entrance of the main tunnel and each vein has been developed separately.
Shepherd and Murphy [48/074909]
The Shepherd and Murphy mine, later referred to as the Moina Tungsten-Tin mine, is situated on the south bank of Bismuth Creek at Moina.
This mine has contributed the greatest part of the total production of tin, tungsten and bismuth from the Moina and Roland Mount districts. During periods of intermittent production between 1893 and 1957, an estimated 525 t Sn, 255 t WO3 and 71 t Bi have been recovered from the underground and surface workings at this mine.
The lode deposits of the Shepherd and Murphy mine were discovered in 1893 by Thomas Shepherd and Thomas Murphy. Shepherd was also one of the discoverers of the silver-lead deposits in Claude Creek (later to become the Round Hill mine). During the early stages of prospecting and mine development, production was intermittent, but from 1907 to 1918 regular production of tin, tungsten and bismuth was maintained. Prior to 1914, mining was confined to the lodes above no. 3 adit, but by 1915 the main shaft had been sunk below that level to a depth of 52 m. From this period up to 1919, no. 4 and 6 lodes, together with the north-west branch of the latter, were developed from the shaft levels, the greater part of stoping being carried out on no. 6 lode. In 1919 a bushfire destroyed the milling plant and the mine closed down.
The erection of a new mill commenced in 1921 by the Shepherd and Murphy Syndicate Limited and was completed in the following year by the New Shepherd and Murphy Mining Company. The latter company milled some 2,000 t of ore, principally from broken material in stopes above no. 3 adit and from surface dumps, for a return of approximately 22 t of concentrate. The shaft levels were not de-watered and operations ceased in 1924.
Between 1933 and 1950, J. P. Godwin carried out intermittent sluicing operations on alluvial and detrital deposits and a limited amount of underground stoping and prospecting.
In 1953, the Moina Tungsten Tin Mining Co. N.L. was formed and by 1954 had de-watered the mine, erected a new treatment plant and had treated some 2540 t of ore. Production continued for the next two years, but in 1957 production ceased and the company was placed in liquidation.
In the petition to the court for liquidation, the directors stated that due to low metal prices they were unable to operate at a profit.
The mine has been abandoned since 1957, but sporadic interest has been shown in the deposit (eg Reid, 1971).
All Nations (Lady Barron) [48/086904]
Early reports of the All Nations mine, situated at the head of Narrawa Creek about 1.5 km east of Moina, were prepared by Twelvetrees (1908,1913), referring to the Lady Barron workings, Reid (1919), Keid (1943) and Nixon (1945).
The veins have been worked over a considerable distance, the surface workings extending for approximately 350 m as a long open cut (or underhand stope). The veins have also been mined on two adit levels, with stopes extending to the surface, and a third internal level connected to the surface by a shaft.
Recorded production from the All Nations mine is 36.253 t WO3 and 0.528 t Bi during the period 1910-1942.
Pig and Whistle (Lawson and Rileys) [48/090900]
At the Pig and Whistle workings, situated about 500 m south-east of the All Nations mine, two intersecting vein systems have been developed on two adit levels 9 m apart.
Pochins [48/091904]
An adit has been driven on a series of rich pockets and short irregular veinlets. The veins were originally considered to be the eastern extension of the All Nations lode (Twelvetrees, 1913; Reid, 1919) but this is not possible.
Lawkemlaw (Burford and Bilson) [48/086901]
Situated approximately 250 m south of the All Nations mine, on the crest of the hill, are the inaccessible workings of the Lawkemlaw mine.
These workings consist of 5 shafts spread over a distance of 100 m along a general bearing of 290°.
Immediately to the south-west of Lawkemlaw mine are several prospecting trenches. These workings are referred to as the Nicholls and Smith tribute by Nixon (1954).
Povey and Johnsons (Sullivans) [48/111913]
To the north of Sayers prospect, on the south bank of Narrawa Creek.
The grade of the vein is apparently reasonably high.
Fletchers [48/032907]
Cropping out on rock benches cut into the banks of the River Lea near Fletchers adit.
The veins are of no economic significance (Reid, 1927; Keid, 1943; Burns, 1959).
Stormont Area
There are two occurrences of bismuth bearing skarn in the valley of the River Lea, about 3.5 km west of Moina. These are the Stormont bismuth mine, located on the west bank of Castle Creek [48/026903] and immediately south-west of Fletchers adit on the banks of the River Lea. Only the disseminated ore in the skarn at Castle Creek has been mined. The Castle Creek deposit was worked from an open cut, from which several short exploratory adits and shafts were driven.
Iris (Kemps Rainbow, Red Robin) [48/083898
Recorded production during intermittent periods of mining between 1912 and 1942.
Yorks [48/117902]
Minor amounts of cassiterite and wolframite have been sluiced from a flat area in the valley of Dolcoath Creek which was probably an old terrace of the River Forth.
A little wolframite is also reported to have been recovered from workings in the creek further to the west.
TIN
Falls mine [48/133902]
The discovery of tin at this location was made about 1918. The mine is situated just above a road cutting on Olivers Road, about 100 m west of Tin Spur Creek.
Only a few meters of these workings are now visible in the open cut.
Such concentrations are extremely erratic and unlikely to be of economic importance.
Lower Workings
The majority of work carried out at Tin Spur was in connection with these deposits. A number of lodes were worked in the vicinity of the old road on the western side of Tin Spur (Ashworths) [48/126907] and also on the nose of Tin Spur itself between the old and the new roads (Goreys and Duffs) [48/127906].
Reid (1919) described another lode, the Star of Peace lode, which contained rich pockets of gold.
The original discovery of tin in this vicinity was made about 1889 and the ore bodies were explored sporadically for about 35 years before being finally abandoned. The lodes have been regarded as an extension of the Falls line of lode. However, it is unlikely that those lodes persist for that distance, and the deposits are more likely to be isolated ones associated with fractures and brecciation close to the Tin Spur Creek Fault.
The workings have long been abandoned and are now inaccessible.
COPPER
Barrington (Alma) [49/219141]
The Barrington (or Alma) copper mine is situated on the north bank of Barrington Creek about 500 m upstream from its confluence with the River Forth (Lake Paloona). The mine was reported on by Thureau (1881) and Twelvetrees (1906, 1909b) and by Blake (1928). The deposit has been explored and developed by means of a shallow shaft and an adit driven 130 m into the hillside. A second smaller adit (the Devonport tunnel) is located 50 m upstream from the main adit. The only recorded production is 457 kg of copper ore (Twelvetrees, 1906).
Lucas and Perrys
Lucas and Perrys lodes are situated about 1.5 km south-west of the Barrington mine [about 49/205130]. A shaft about 12 m deep has been sunk on each of two outcrops of gossan up to 6 m wide and about 40 m apart.
Crawfords
Crawfords lodes, situated near Alma at the confluence of the Wilmot and Forth Rivers.
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Comments:
darren knowles
increadable history verry interesting well put together
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