Lady Bountiful Gold Mine, Mount Pleasant, Black Flag Goldfield, Kalgoorlie-Boulder Shire, Western Australia, Australia

Latitude & Longitude (WGS84): | 30° 30' 18'' South , 121° 12' 43'' East |
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Latitude & Longitude (decimal): | -30.50508,121.21204 |
GeoHash: | G#: qdw4qnxzj |
Locality type: | Mine |
Köppen climate type: | BSh : Hot semi-arid (steppe) climate |
Lady Bountiful is in the northern section of the Mount Pleasant complex, with Lady Bountiful Extended immediately north, and Golden Kilometre and G.K. Shoot to the south. Historically the deposit was mined as shallow open pits, and underground workings, but in modern times its refers to sinuous shallow open pits following palaeochannels, much like the Lady Bountiful Extended mine. The workings are largely abandoned. 4.79 Mt at 1.75 g/t yielding 269 000 ounces of gold was mined.
Gold is found along a quartz veined, sinistral, brittle fault zone at the boundary between the Liberty Granitoid and Mount Pleasant Sill.
The open pits here are in a unit called the Liberty Granite, which is a massive, coarse equigranular biotite-hornblende adamellite, east of its contact with the differentiated Mount Pleasant sill. The Lady Bountiful ore lode runs east-west, dipping 75-85 degrees north as quartz veins 2-3 metres wide. North and south-east of this is vein stockwork 500 x 100 metres. All hosts gold mineralisation. Gold is found in primary and secondary ore.
In the Mount Pleasant sill the main lode is associated with pyrite in quartz veins. Within the Liberty Granite gold is found in carbonate-quartz veins with coarse pyrite, chalcopyrite, pyrrhotite, galena, sphalerite, and Au-Ag-Bi-Pb tellurides in sericite, K feldspar and albite altered adamellite.
Narrow less than 1 metre bleached wallrock has an alteration envelope to the fault zones consisting of albite-K mica-chlorite-calcite-rutile.
Secondary ore is found as channel deposits consisting of clasts of quartz and as residual gold at 30 metres deep in granite sand and saprolite. The gold has been derived from quartz veins where the gold has precipitated at a palaeo water table.
The deposit was mined initially from 1896 to 1909 as a small scale underground operation. Large scale open pits were developed from 1985 to 1988, and then an underground decline 1988 until around 1992.
The mine was about 5 kilometres north of the former Black Flag township. The leases were under offer to R.H. Henning, who then floated The Lady Bountiful Gold Mining Company in Coolgardie and the eastern seaboard of Australia in 1895 with 50 000 pounds capital. Alexander Forrest (Mayor of Perth), and James Shaw (Mayor of Coolgardie) were two of the directors. It was formed to acquire the leases 408, 409, and 500, 12 acres each. The vendor got 5000 pound cash and 20 000 fully paid shares.
At the time the leases contained five shallow shafts and much minor shallow alluvial diggings along the line of lode. The gold was described as fine but thickly impregnating the stone. The eastern lease contained shafts and costeans on a reef 3 feet wide, in a lode with quartz stringers and leaders. The central lease showed the reef outcropping boldly in parts, with several shafts down to a maximum depth of 30 feet. The reef here was 3 to 4 feet wide, and gold was reported thickly studding the rock. The west lease showed the reef as a low outcrop with shafts and costeans down to 20 feet.
A 10 head battery was erected in 1897. Carr (surname) was the original mine manager but left shortly after the battery was commissioned over a disagreement on the number of men the company would employ for development work. There was also a cyanide plant capable of 550 tonnes per month. In its first 18 months the mine had produced 2578 tonnes of ore for 3228 ounces of gold. At least 104 tonnes of this was telluride, producing 417 ounces at 17 dwt.
By 1900, operations were at a standstill, either poor spending by management and/or patchy gold values. The mine was possibly let on tribute, and one source states it was active until 1909, but no information was found after 1899.
Commodity List
This is a list of exploitable or exploited mineral commodities recorded at this locality.Mineral List
16 valid minerals.
Rock Types Recorded
Select Rock List Type
Alphabetical List Tree DiagramRegional Geology
This geological map and associated information on rock units at or nearby to the coordinates given for this locality is based on relatively small scale geological maps provided by various national Geological Surveys. This does not necessarily represent the complete geology at this locality but it gives a background for the region in which it is found.
Click on geological units on the map for more information. Click here to view full-screen map on Macrostrat.org
Archean 2500 - 4000 Ma ID: 891684 | mafic intrusive rocks 74263 Age: Archean (2500 - 4000 Ma) Description: Mafic intrusive rocks, medium to coarse-grained; layered mafic to ultramafic intrusions - dolerite, gabbro, olivine gabbro, peridotite, pyroxenite, leucogabbro, quartz dolerite, quartz gabbro, gabbronorite Comments: igneous mafic intrusive; synthesis of multiple published descriptions Lithology: Igneous mafic intrusive Reference: Raymond, O.L., Liu, S., Gallagher, R., Zhang, W., Highet, L.M. Surface Geology of Australia 1:1 million scale dataset 2012 edition. Commonwealth of Australia (Geoscience Australia). [5] |
Neoarchean - Mesoarchean 2500 - 3200 Ma ID: 3187518 | Archean volcanic rocks Age: Archean (2500 - 3200 Ma) Comments: Yilgarn Craton Lithology: Greenstone belt; mafic-ultramafic volcanic rocks Reference: Chorlton, L.B. Generalized geology of the world: bedrock domains and major faults in GIS format: a small-scale world geology map with an extended geological attribute database. doi: 10.4095/223767. Geological Survey of Canada, Open File 5529. [154] |
Data and map coding provided by Macrostrat.org, used under Creative Commons Attribution 4.0 License
References
External Links
http://www.nortongoldfields.com.au/Projects_Exploration_MtPleasant.htm