Latitude & Longitude (WGS84):	30° 26' 55'' South , 121° 35' 45'' East
Latitude & Longitude (decimal):	-30.44874,121.59604
GeoHash:	G#: qdw6ybzx1
Locality type:	Mine
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 List

This is a list of exploitable or exploited mineral commodities recorded at this locality.

Mineral List

4 valid minerals.

Rock Types Recorded

Regional 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: 765794

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; Comments: igneous volcanic; igneous felsic volcanic; synthesis of multiple published descriptions Lithology: Igneous volcanic; igneous felsic volcanic 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