|Latitude & Longitude (WGS84):||41° 46' 59'' South , 145° 31' 0'' East|
|Latitude & Longitude (decimal):||-41.78306,145.51667|
|Köppen climate type:||Cfb : Temperate oceanic climate|
A Zn-Pb-Cu-Ag-Au VMS-type deposit on the slopes of Mt Black in western Tasmania. The deposit was discovered in 1893 but not worked on a large scale until 1936 due to the very fine grain size of the intimately combined sulphides. The underground mine is still in operation today ('MMG Rosebery Mine'), with an expected mine life of >2020. It has previously been operated by several other companies, initially EZ (Electrolytic Zinc), later Pasminco, Oz Minerals and Zinifex, recently taken over by MMG.
The mine has the capacity to produce approximately 700,000 tonnes of ore a year, which is then processed into zinc concentrate, lead concentrate, and gold and silver doré. It also produces a small amount of copper concentrate.
The ore is a volcanic-related (Mt. Read volcanics), sediment-hosted, pyrite-rich massive sulphide, with numerous discrete orebodies, but no gossans. There has been some overprinting by Devonian granites, related to an underlying granite intrusion. This has resulted in some unusual mineralisatio zones, including magnetite, biotite, spessartine, danalite, rhodonite, etc.
Mineralogically, it is best known for its vein minerals, mostly barite and other barium minerals, plus rhodochrosite and boulangerite.
Commodity ListThis is a list of exploitable or exploited mineral commodities recorded at this locality.
56 valid minerals.
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
443.8 - 485.4 Ma
|Paleozoic sedimentary rocks|
Age: Ordovician (443.8 - 485.4 Ma)
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. 
|Early Ordovician - Guzhangian|
470 - 500.5 Ma
|Denison Group and correlates|
Age: Paleozoic (470 - 500.5 Ma)
Stratigraphic Name: Denison Group
Comments: sedimentary siliciclastic; synthesis of multiple published descriptions
Lithology: Sedimentary siliciclastic
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).