Big Cadia

Porphyry copper (Cu-Au) deposit in New South Wales, Australia

Names and other identifiers

GMRAP ID 4042
Alternate names Iron Duke
Tract name Macquarie (009pCu8002)
Group name Cadia Group
Included sites Group includes Big Cadia, Cadia East open pit, Cadia East underground, Cadia Far East, Cadia Hill open pit, Cadia Quarry, and Ridgeway deposits and Little Cadia prospect.
Site status deposit

Geographic location

Country Australia
State or province New South Wales
Geographic location 148.9895, -33.4396
Geologic map unit 148.9895, -33.4396
Nearby data

Geologic information

Deposit type Porphyry copper
Deposit subtype Cu-Au
Age (Ma) 438.2Ma
Age determination method Ar-Ar muscovite
Age range 438.2 ±2.7 Ma
Age reference Forster and others (2004, p. 779–780)
Minerals actinolite, calcite, chalcopyrite, chorite, epidote, hematite, magnetite, sericite
Associated rocks limestone in shoshonitic volcaniclastic and sedimentary rocks, shoshonitic monzonite, clinopyroxene-hornblende quartz monzodiorite, and quartz monzonite porphyries
Tectonic setting island arc
Stratigraphic age Early Silurian

Commodity and development information

Development status Prospect
Major commodities Cu, Au
Tonnage (Mt) 42Mt
Cu grade (%) 0.398%
Au grade (g/t) 0.381g/t
Contained copper 168,000t
Gold-Moly ratio -9999

Reference information

Comments Location, tonnage and grade of indicated + inferred resources from Geoscience Australia (2010); tonnage and grade combined for Big Cadia and Little Cadia. Cu-Au skarns related to porphyritic intrusions.
Study area name Australia
References Forster and others (2004); Holliday and others (2002); Cooke and others (2007); Wilson, Cooke, Harper and Deyell (2007); Wilson, Cooke, Stein, and others (2007); Geoscience Australia (2010)
Site reference Bookstrom and others (2014)
Cooke, D.R., Wilson, A.J., House, M.J., Wolfe, R.C., Walshe, J.L., Lickfold, Vanessa., and Crawford, A.J., 2007, Alkalic porphyry Au-Cu and associated mineral deposits of the Ordovician to Early Silurian Macquarie arc, New South Wales: Australian Journal of Earth Sciences, v. 54, p. 445–463. (Also available at http://dx.doi.org/10.1080/08120090601146771.)Forster, D.B., Seccombe, P.K., and Phillips, David, 2004, Controls on skarn mineralization and alteration at the Cadia deposits, New South Wales, Australia: Economic Geology, v. 99, p. 761–788. (Also available at http://dx.doi.org/10.2113/gsecongeo.99.4.761.)Geoscience Australia, 2010, Australian mines atlas: Geoscience Australia Web page accessed October 20–December 27, 2010, at http://www.australianminesatlas.gov.au/.Holliday, J.R., Wilson, A.J., Blevin, P.L., Tedder, I.J., Dunham, P.D., and Pfitzner, Michael, 2002, Porphyry gold-copper mineralization in the Cadia district, eastern Lachlan fold felt, New South Wales, and its relationship to shoshonitic magmatism: Mineralium Deposita, v. 37, p. 100–116. (Also available at http://dx.doi.org/10.1007/s00126-001-0233-8.)Wilson, A.J., Cooke, D.R., Harper, B.J., and Deyell, C.L., 2007, Sulfur isotopic zonation in the Cadia district, southeastern Australia—Exploration significance and implications for the genesis of alkalic porphyry gold-copper deposits: Mineralium Deposita, v. 42, p. 465–487. (Also available at http://dx.doi.org/10.1007/s00126-006-0071-9.)Wilson, A.J., Cooke, D.R., Stein, H.J., Fanning, M.C., Holliday, J.R., and Tedder, I.J., 2007, U-Pb and Re-Os geochronologic evidence for two alkalic porphyry ore-forming events in the Cadia district, New South Wales, Australia: Economic Geology, v.102, p. 3–26. (Also available at http://dx.doi.org/10.2113/gsecongeo.102.1.3.)