Sulphides have a simple formula, and show properties exhibited by metals, like luster and conductivity. Sulfides are identified by the anion –S-2 (Britannica). Like Sulphides and sulphates, carbonates are also non-silicates. The carbonates are one of those minerals which are not localized and found in abundance and are distributed far and wide (GeoSci). When a carbonate ion, CO32- , is present in any mineral family it s referred to as a carbonate mineral.
Iron sulphide, also known as pyrite has the chemical formula FeS. More commonly it is also referred to as the Fool’s Gold (GeoSci). It is found in Illinois, Wisconsin, Missouri, and Grant county (Galleries).
Q. 2. There are a number of mines which have been developed in different parts of the world which now release acid mine drainage (AMD). For the following three mines or mine districts, 1) Iron Mountain Mine in Shasta County, Redding, California, 2) Britannia Mine in Britannia Beach, British Columbia, Canada, and 3) the Rio Tinto mining district near Huelva, Spain, describe the years of operation, the type of ore mined, and the scale and nature of wastes generated from the mining activities.
1. Iron Mountain Mine in Shasta County, Redding, California: iron, gold, silver, zinc, copper and pyrite were mined. The mine operated from the 1860’s up to 1963. The mine generated cadmium, copper, zinc, copper compounds, zinc compounds as wastes, which contaminated the Sacramento River. Richmond mine has the highest acidic mine water; with pH values as low as -3.6, metal concentrates 200g/L, and sulphate concentrates 760g/L.
2. Britannia Mine in Britannia Beach, British Columbia, Canada: was a copper mine, which operated from 1900 to 1974. It also generated zinc sulphide and pyrite (Mills). Intertidal discharge from the mine resulted in sub-aqueous deposits in Howe Sound, which was in excess of 44 million tones. Also 980 mg/l