Properties of Tungsten:

        Major minerals of tungsten are essentially of two categories. The first is wolframite [(Fe, Mn)WO₄], which contains iron and manganese tungstates in all proportions between 20 and 80 percent of each. The second is Scheelite  (CaWO₄), which fluoresces a bright bluish color under ultraviolet light.
        After grinding and cleaning, the ores are treated with alkalis to yield tungsten trioxide (WO3). The trioxide is finally reduced with carbon or hydrogen gas to produce the pure metal.

Using carbon as the reducing agent, the reaction is:

(tungsten trioxide  + carbon + heat      tungsten metal  + carbon dioxide)

Or using hydrogen gas as the reducing agent:                                                      

tungsten trioxide + hydrogen gas + heat    tungsten metal + water vapor)

Some Compounds of Tungsten:

Tungsten's principal oxidation state is +6, although there are a few stable compounds having lower oxidation states. Generally, tungsten compounds look like this:

Tungsten hexachloride, WCl₆

Tungsten trioxide , WO₃

There is also a tendency to form tungsten oxychlorides, WOCl₄ and WO₂Cl₂:

One of the lower oxidation states, namely,   +4, occurs in the hard, commercially valuable abrasive, tungsten carbide, WC:

  All information from Exploring Chemical Element and their Compounds