Types of Minerals and Ores

Some of the ores are secondary from the molybdenum point view. This means that the main minerals are copper pyrites and other copper minerals They have been formed from copper-rich solutions containing small amounts of molybdenum, which have penetrated the rocks at high temperature and pressure. The solutions have been heated by magma. During the subsequent coohng the minerals have been formed as deposits along cracks in surrounding rocks. 

Important examples of such ores are Bingham Canyon in Utah, USA, Sierita in Arizona, USA, and most importantly Chuquicamata in Chile. This mine is situated in Northern Chile on the western slopes of the Andes. It has an open pit, 2 3 km, with a depth of 800 m. and is one of the biggest copper mines in the world. About 600 000 tonnes of ore are mined daily. 

A very large deposit of the same type was recently discovered in Quartz Hill east of Ketchikan in Alaska. It contains 0.1% MoS.  

In Knaben in Norway in a slaty granite interwoven by quarts veins, a molybdenum ore with 0.15-0.20% MoS is available. During World War I, German, British, French and Russian armament manufacturers competed to buy molybdenum from this single European source. The mining in Knaben has, however, stopped since the very big deposits in North and South America have been exploited. 

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