Coalstoun

Porphyry copper deposit in Queensland, Australia

Names and other identifiers

GMRAP ID 565
Alternate names Coalstoun Lakes
Tract name East Tasmanide - Central sub-tract (009pCu8004b)
Site status deposit

Geographic location

Country Australia
State or province Queensland
Geographic location 151.83, -25.6168
Geologic map unit 151.83, -25.6168
Nearby data

Geologic information

Deposit type Porphyry copper
Age (Ma) 235Ma
Age determination method K-Ar
Age range 235 ±4 Ma
Age reference Ashley and others (1978)
Minerals actinolitic hornblende, albite, anhydrite/gypsum, biotite, bornite, carbonate, chalcocite/digenite, chalcopyrite, chlorite, covellite, chrysocolla, epidote, fluorite, galena, goethite/limonite, hematite/specularite, kaolinite, magnetite, malachite, molybdenite, neotocite, pyrite, rutile, sericite, sphalerite, tremolite-actinolite, tourmaline, turquoise
Associated rocks mafic to felsic metavolcanic rocks, meta-andesite, meta-basalt, siliciclastic metasedimentary chert, graywacke, shale, siltstone, diorite porphyry, quartz diorite, tonalite porphyry, trondhjemite, granodiorite porphyry, dacite porphyry, breccia pipes
Tectonic setting continental margin
Stratigraphic age Middle Triassic

Commodity and development information

Development status Prospect
Major commodities Cu
Minor commodities Au, Mo
Trace commodities Ag
Tonnage (Mt) 80Mt
Cu grade (%) 0.3%
Contained copper 240,000t
Gold-Moly ratio -9999

Reference information

Comments Location, tonnage and grade of inferred resources, reported by Geoscience Australia (2010). Exposed porphyry-related stockwork of fracture-filling quartz-pyrite-chalcopyrite veinlets; locally up to 0.015% Mo (Ashley and others, 1978). Ore area 1.8 square km, alteration A axis 1.1 km, B axis 0.8 km, alteration area 1.2 km, sulfide A axis 0.7 km, B axis 0.7 km. Fracturing weak to moderate. Lower to mid part exposed. Secondary enrichment locally strong. Includes 7.7 Mt at 0.6% Cu in shallow supergene sulfide zone. Central altered zone of biotite-orthoclase-albite-magnetite, mineralized with pyrite-chalcopyrite-molybdenite. Outer zone of quartz-sericite-pyrite. Retrograde propylitic assemblage overprints other zones.
Study area name Australia
References Ashley and others (1978); Horton (1978); Murray (1990); Singer and others (2008); Ewers and others (2002); Geoscience Australia (2010); Geological Survey of Queensland (2010)
Site reference Bookstrom and others (2014)
Ashley, P.M., Billington, W.G., Graham, R.L., and Neale, R.C., 1978, Geology of the Coalstoun porphyry copper prospect, southeast Queensland, Australia: Economic Geology, v. 73, p. 945–965. (Also available at http://dx.doi.org/10.2113/gsecongeo.73.5.945.)Ewers, G.R., Evans, N., and Hazell, M., (Kilgour, B., comp.), 2002, OZMIN Mineral deposits database [Digital Datasets]: Canberra, Geoscience Australia, metadata accessed September 3, 2013, at http://www.ga.gov.au/meta/ANZCW0703003393.html.
Geological Survey of Queensland, 2010, Mineral occurrence and geology observations: Queensland Government, Department of Employment, Economic Development and Innovation (digital dataset on DVD).
Geoscience Australia, 2010, Australian mines atlas: Geoscience Australia Web page accessed October 20–December 27, 2010, at http://www.australianminesatlas.gov.au/.Horton, D.J., 1978, Porphyry-type copper-molybdenum mineralization belts in eastern Queensland, Australia: Economic Geology, v. 73, p. 904–921. (Also available at http://dx.doi.org/10.2113/gsecongeo.73.5.904.)
Murray, C.G., 1990, Tasman fold belt in Queensland, in Hughes, F.E., ed., Geology of the Mineral Deposits of Australia and New Guinea: Australasian Institute of Mining and Metallurgy, Monograph Series, v. 2, no. 14, p. 1431–1450.
Singer, D.A., Berger, V.I., and Moring, B.C., 2008, Porphyry copper deposits of the world—Database and grade and tonnage models, 2008: U.S. Geological Survey Open-File Report 2008-1155, [45] p. and digital data, accessed December 31, 2013, at http://pubs.usgs.gov/of/2008/1155/.