Greisen is a highly-mechanized granite or pegmatite. Greisen is usually a coarse crystalline rock, rich in halide minerals such as fluorite and sometimes metal oxides, sulfides or borates and rare minerals like beril and topaz. Petrology
Greases result from the endoskarne conversion of molten granite during interaction with hydrothermal fluids. These liquids and gases are the last magmatic liquids released during the crystallization of a granite intrusion. Possible mineral compositions of greisens are: Preventing conflicts
Greas can occur in the earth's crust to a depth of 5 km. They are generally associated with phosphorus-rich clotting rocks such as diorite. Greisens are interesting to the exploration industry because the last hydrothermal fluids in granite crystallization are often enriched in incompatible elements such as potassium, tin, tungsten, molybdenum and fluorine, as well as metals such as gold, silver, and occasionally copper.
Examples of economically viable phenomena are:
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