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Main/Minor Ore Minerals |
Trace Minerals |
Tonnage, Grade, Continuity |
Beneficiation and Results |
Metals
in ‘Smelter Charge’ |
Bronze Age Ores |
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1a Copper-veins 1b Copper-vugh infilling |
Chalcopyrite, malachite, copper-bearing limonite. Coarse-grain size. Few intergrowths |
Copper sulphide-digenite, djurleite, covelline, spionkopite. Copper-oxides – Cuprite, tenorite. Native copper, sphalerite, manganese oxides. |
High Tonnage, continuous. Approx. 10% Cu metal. High tonnage, discontinuous. 10% Cu metal or less. |
High grade chalcopyrite-malachite ± Cu-bearing limonite concentrate by hand-cobbing. |
Cu, Fe, trace Ni, Ag, Mn |
By-product Bronze-Age Ores? |
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2a Copper ddu |
Amorphous iron-copper-bearing oxides/hydroxides. Minor malachite. Powdery |
None |
Tonnes, locally, discontinuous. <5% Cu metal? |
Beneficiation not possible. |
Fe, Cu, trace Co, Mn, Ni As. |
2b Azurite-shales |
Azurite nodules <1cm, minor malachite. |
Chalcopyrite, pyrite. |
Very local. Continuous. < 2% Cu. |
High grade Azurite concentrate. |
Cu, trace Fe. |
Non Copper Ore Assemblages |
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3a Polymetallic disseminated sulphides |
Chalcopyrite, galena, siegenite, pyrite, marcasite. Fine-grained, complex intergrown sulphides. |
Cobaltite/gersdorffite, malachite, azurite, tennantite, sphalerite. |
Very little? No in situ ore seen. <5% Cu |
Fine-grained separate copper concentrate not possible. |
Fe, Cu, Co, Pb, trace Ni, Zn, As. |
3b Galena-veins |
Galena, minor chalcopyrite. Coarse-grained galena. |
Malachite, nickeliferous pyrite, marcasite, millerite, sphalerite. |
Little tonnage. Continuous but localized. <1% Cu metal. |
Lead concentrate by hand cobbing. Copper concentrate not possible. |
Pb, Cu, Fe, trace Ni, Co, Ag, Zn. |