Secondary Galena on Wurtzite – Broken Hill NSW
A stunning piece of Broken Hill history is this Secondary Galena & Wurtzite. It displays stacked growth cubes of Galena with the lower sections coated by creamy yellow Wurtzite.
A rare specimen from Brownes Shaft, Broken Hill and one of which many people say is arguably the finest place of secondary galena in the world.
Broken Hill is famous for its mining which started around 1883 and soon uncovered immense riches of silver, lead and zinc. The wealth generated from the mining of this ore-body has contributed significantly to Australia’s economy.
This interesting specimen comes from Brownes Shaft and mining reports in the Argus identify the main shaft as “the Penglass shaft”; this is likely to have been renamed Brownes Shaft.
The other large shaft was Macintyre and there were also the King and North shafts. In 1962 the British Section (including the Junction Mines and Block 14) were closed and sold to Broken Hill South Limited. In 1972 they ceased work at Browne Shaft.
Wurtzite, a zinc iron sulfide mineral with composition (Zn,Fe)S is named after the French chemist C.A. Wurtz (1817-1884). It forms as brown tabular or platy hexagonal crystals, six sided pyramids, radiating acicular crystals or as botryoidal crusts. As a result, it occurs close to metal ore deposits and is often found in association with galena, sphalerite and pyrite.
This specimen comes from the collection of Kenneth Hartnett who from the information I gathered was an underground Broken Hill miner around the 1950’s.
I acquired the specimen from Tony Forsyth of Mineral Store Australia at the 2018 Bankstown Gem and Mineral Fair.
This specimen is so uncommon, I haven’t been able to find much information on both the specimen itself as well as who exactly Kenneth Hartnett was. I would love to be able to find out his role in preserving this fantastic piece of Broken Hill mineralogical history. If you are reading this and have any information to contribute, please get in touch as it would be very much appreciated.
Chemical Formula: PbS (Galena) (Zn,Fe)S (Wurtzite)
ID #: JG0182
Colour: Grey, green, yellow, brown
Hardness: 3.5 – 4
Acquisition Date: 02/06/2018
Crystal System: Isometric/Hexagonal
Location: Brownes Shaft – Broken Hill NSW, Australia
Rarity of Mineral