Historical information
Majority of Galena in Australia is found in hydrothermal deposits emplaced around 1680 million years ago which have been heavily metamorphosed. Galena is the natural mineral form of lead sulfaide. It occurs generally as fine to large crystals due to syntectonic remobilization at low temperatures and moves to a suitable location.
The colour is a shining lead and silvery gray with high specific gravity between 7.2 and 7.6 gms/cm3 and contains 86.6 lead sulfaide in its purest form. Its cyrstal system is cubic with perfect cleavages, and contract penetration and lamellar twinning.
This particular specimen is from the Broken Hill mine, it is one of the largest lead mines located in Western New South Wales and still has ore reserves amounting to 20.9 million tonnes of ore grading of 7.4% lead, 9.4% zinc, and 61.5 million oz of Silver. Throughout its history, it has produced over 200 million tonnes of ore throughout its 127 years of mining history dating back to 1885.
Significance
Galena mineral ore found in Australia is considered rare, as it is only currently found in the Broken Hill Mine of Western New South Wales. It represents heritage value through the systematic collecting of the geological surveyers in Victoria and Australia during the early to late 19th Century. The fact that it is only found in one mining area of Australia, shows that this specimen is rare for examples of Australian Galena.
This mineral specimen is one part to a larger collection, aquistion, and distribution of Garnet in Galena around Australia and parts of the world and donated to the Burke Museum between 1860-1880. While this specimen was not found by the Victorian Geological Survey, it shows the historical need for mapping geological areas around the Gold Rush region to further identify areas of precious metal and gem aquisition. Additionally, collecting these specimens was an important part of mapping the scientific make up of the earth's surface. Many were sent to institutions for further contribution to research and scientific knowledge of the specimens.
Physical description
A solid coin-sized lead and zinc sulphaide and zinc silicate ore mineral in shades of black and red with shiny black points.
Inscriptions & markings
GARNET CRYSTALS in / GALENA (lead sulphide), / SPALERITE (zinc sulphide), / WILLEMITE (zinc silicate) ore. / Locality: Broken Hill, NSW
Subjects
References
- Lead Sulfaide A research paper on the scientific aspects of Galena mineral.
- Economic Geology A reseach paper on the scientific aspects of Australian Galena.
- Perilya Broken Hill Mine history.
- Museums Victoria Collections - Geology Webpage detailing the geological specimens in Museums Victoria collections.
- GeologyScience - Galena Webpage detailing the scientific aspects of the Galena mineral.
