|Latitude & Longitude (WGS84):||30° 26' 55'' South , 121° 35' 45'' East|
|Latitude & Longitude (decimal):||-30.44874,121.59604|
|Köppen climate type:||BWh : Hot deserts climate|
The Gordon Sirdar is approximately 20 kilometres north of Kanowna.
Gold is hosted in an intensely deformed mafic-intermediate fragmental sequence. The main mineralisation is found in quartz-carbonate-fuchsite as discontinuous elongate pods, parallel to the main shear foliation. The pods plunge steeply and coalesce at depth into two main ore zones.
The highest grades of gold is found in fuchsite altered fragmental zones, close to the contact of an otherwise barren felsic porphyry intrusion adjoining to the east. Gold is found as free grains and enclosed in pyrite. The mine has a high silver-gold ratio, but gold is not found associated with the silver.
The deposit is part of the regionally significant north-west to south-east trending, steeply dipping, Sirdar Shear Zone, over 500 metres wide in the immediate area.
Historic production from 1899 to 1950 is 42 842 tonnes averaging 11.27 g/t for 16 610 ounces of gold, mainly as underground operations. An open cut was developed between June 1999 to May 2000 yielding 91 243 tonnes at 6.26 g/t for 18 341 ounces.
The mine was originally developed by English based General Gordon Gold Mining Company. After spending vast sums on machinery, high salaries etc, they processed only 40 tonnes of ore before abandoning the property around 1900. Soon after the Williams brothers took over for the next seven years, producing 8000 pounds in gold money wise in early 19th Century figures.
The Sirdar Company then took over around 1909, erecting a mill, and were active for the next three years. A Kalgoorlie syndicate took over in 1917.
After being idle for many years, Frederick Henry Leslie and Ernest Hunter arrived at the mine late 1936. They erected six cyanide vats and began processing the extensive tailings. A Huntington mill was installed in 1939, and they moved into mining the low grade oxide ore remaining. GML 1532X. Information was found to 1940 on their activity, although other sources state the mine was active sporadically to 1981.
FMR Investments (formerly Barminco Pty Ltd) began extending the open pit late 2011, and some underground mining followed.
Commodity ListThis is a list of exploitable or exploited mineral commodities recorded at this locality.
4 valid minerals.
Rock Types Recorded
Select Rock List TypeAlphabetical List Tree Diagram
Entries shown in red are rocks recorded for this region.
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
2500 - 4000 Ma
|felsic volcanic and volcaniclastic rocks 74288|
Age: Archean (2500 - 4000 Ma)
Description: Quartz-feldspar (meta-) porphyry, porphyritic microgranite; rhyolite, dacite, rhyodacite, andesite; agglomerate, breccia tuff; felsic schist; felsic volcanic and volcaniclastic rocks; dacite and rhyodacite tuff; dacite porphyry;
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). 
|Neoarchean - Mesoarchean|
2500 - 3200 Ma
|Archean volcanic rocks|
Age: Archean (2500 - 3200 Ma)
Comments: Yilgarn Craton
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.