Geology Formation of Ore Deposits

This model (see Fig. 2.2) starts with any magma of changing composition and of different sources. Changes in chemical and physical properties take place. Moving occurs sometimes to higher levels of the earth crust, and consequently temperature as well as pressure gradually drop and differential crystallization starts. The first crystallization step 

Landolt Bdmstein, Numerical Data and Functional Relationships in Science and Technology, Group VI, Vol. 2 Astronomy and Astrophysics, Subvol. a (K. Schaifers and H. H. Voigt, eds.) Springer-Verlag, Heidelberg (1981). 

Grevesse and E. Anders, Solar Element Abundances in Solar Interior and Atmosphere (A. N. Cox, W. C. Livingston, and M. S. Mathews, eds.). The University of Arizona Press, Tucson (1991). 

It is generally believed that tungsten is bom in mineralizing fluids chiefly as tungstate ion, tungstic acid, sodium tungstate, or as heteropoly acid. The relative amount of these compoimds depends on temperature, pH, and silica concentration of the solution. Tungsten 

Hydrottwimal liquid containing excessive silica highly enriched In volatiles and different metals 

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