Tungsten - How does it occur?
Tungsten ores occur in the form of scheelite (CaWO₄), a pale translucent mineral, or more readily as wolframite (FeWO₄), a dark bladed mineral oxide.  Scheelite is the predominant tungsten mineral at White Rock.  Scheelite has a high specific gravity (6g/cc) meaning it is heavier than magnetite (5g/cc), and can be separated from most other minerals by utilizing gravity methods, similar to gold nuggets or ores of tin. 

Tungsten Concentrates
Concentrates of scheelite generally grade 60-70% WO₃. The concentrates are later processed at a specialized leach plant to produce a premium tungsten product known as ammonium paratungstate, or APT.   APT is a commonly sold tungsten product in world markets.  During 2006 APT was quoted at around US$250 per MTU (metric tonne unit of WO₃).  One MTU is one hundredth of a tonne contained tungsten trioxide, so one tonne of APT was valued at about US$25,000 during 2006.  Prices have remained strong in 2007. 

Tungsten Properties
Several special properties of tungsten allow it to be used for specific industrial uses.  There are few alternative products that are available to substitute for tungsten.  Some of the special properties of tungsten include:

		The compound tungsten carbide (W2C) is the hardest known substance other than diamond.
		Tungsten metal is very heavy, with a specific gravity of 19g/cc similar to lead and gold.
		The melting point of tungsten is the highest of any metal at around 3400 degrees C.
		Tungsten generally does not break down easily or rust, so it is therefore is considered environmentally friendly relative to other heavy metals such as lead or cobalt.

Tungsten Uses
The predominant use for tungsten is in hard metals (tungsten carbides) such as in high speed cutting tools, drilling bits, milling products, and heavy machinery.  Its high density allows tungsten to be used as ballast, in sporting goods, and in armaments.  Its high melting point allows tungsten to be used for such diverse applications as in jet turbine engines and light bulb filaments. 

Production
China has been the major player in tungsten production for many years.  In the last few years China has produced more than 80% of the world's supply of tungsten, at around 50,000 tonnes per annum.  Due to its rapid economic growth China has now become a net importer, and the price of tungsten more than doubled in 2005 after a 20 year hiatus. 

Suppliers of tungsten concentrates in the west are relatively few.  Minor production comes from Canada, Russia, Austria, Portugal, Bolivia, and Australia.