300 likes | 456 Vues
BASE METALS. Cu, Pb, Zn, Sn, Hg, Cd. Copper. Earliest Underground Mines When ~ 6000 years ago Much of it native Cu Ore mineral: Chalcopyrite. Copper. Abundance is 58 ppm. Copper: Geological Occurrence. Magmatic Segregation Deposit Hydrothermal Sediment Hosted. Copper: Hydrothermal.
E N D
BASE METALS Cu, Pb, Zn, Sn, Hg, Cd
Copper • Earliest Underground Mines • When • ~ 6000 years ago • Much of it native Cu • Ore mineral: Chalcopyrite
Copper • Abundance is 58 ppm
Copper: Geological Occurrence • Magmatic Segregation Deposit • Hydrothermal • Sediment Hosted
Copper: Hydrothermal • 1. Veins • A. meteoric or sea water • B. Magmatic water • E.g. Yellowstone is 90% rain water and 10% magmatic • A little diversion here!
Copper: Hydrothermal • 2. Porphyry Copper • 3. Skarn • 4. Volcanogenic massive sulphide
Copper: Sediment Hosted • Shales • Kupferschiefer • 245 to 286 million years old • 20 cm thick; over 6000 square km • Mined since the 1300’s • Congo and Zambia • 900 million years old • Our source of Co as well • White Pine Cu, UP Michigan
Copper: major producers 2006 • Chile--35% the world’s production • U.S. 8% • Peru 7% • All others under 5%
Lead and Zinc • Usually found together in nature • Have approximately the same solubility in fluids—both relatively low temperature • Pb has been known since antiquity, but not Zn
Lead and Zinc Minerals • Pb—Galena PbS • Zn-sphalerite (Zn,Fe)S • Source of Cd too as by-product • ZnCO3 (original source)
Lead Uses • Gasoline in some countries • Batteries • Paints • Solder • Bearings • Xray Radiation protection
Lead Facts • China and Australia produce about 50% of the world’s lead (2006) • U.S. recycled about 74% of the lead in 2006 • Toxicity
Zinc • Discovered in Bristol in 1740 (your text)—was a Zn industry established • Discovered by Andreas Marggraff in 1746 (web elements) • http://www.zinc.org/# • Relatively soft, bluish white—harder to smelt than either Cu or Pb
Zinc uses • Galvonizing • Zn in brass • ZnO • Cu pennies (since 1982 in the U.S. (in the UK, pennies and tuppences are Cu clad steel)
Zinc: Major Producers • China produced 2.5 million tons • 25% of the world’s production • Australia produced 1.4 million • 14% • Peru produced 1.21 million • 12.1 %
Geologic Occurrence: Lead & Zinc • 1. Veins • 2. Volcanogenic Massive Sulphide • 3. Mississippi Valley Type Deposits • 4. Sediment Hosted
Sn, Hg, Cd • Tin has been known for over 5000 years • Bronze and Pewter • Sn plating • Solders • Mineral: Cassiterite
Geologic Occurrence of Sn • Granitic Rocks • Placer deposits • It is very dense and hard
Tin Producers • USGS http://minerals.usgs.gov/minerals/pubs/commodity/tin/
Mercury (Hg) • Liquid in its natural state • Mineral source: Cinnabar (HgS) • Blood red in color • Mercury data: http://minerals.usgs.gov/minerals/pubs/commodity/mercury/
Cadmium (Cd) • Discovered in 1817 as an impurity associated with Zn • Cd is recovered during the smelting of ZnS • Cd data:http://minerals.usgs.gov/minerals/pubs/commodity/cadmium/