Hypogene Minerals

minerals formed deep in the earth’s crust. Hypogenes include all kinds of minerals: those that crystallize during the cooling of silicate and sulfide-oxide magmatic melts (such as feldspar, pyroxenes, olivine, chromite, and titanomagnetite), those of residual (pegmatite) flows, which are rich in gaseous compounds (micas, topaz, and beryllium), those from contact-metasomatic processes (garnets, idocrase, magnetite, pyroxenes, and scheelite), those of hydrothermal ore veins (fluorite, wolframite, cassiterite, and sulfides of iron, copper, lead, and zinc), and those of volcanic sublimates (sulfur and salmiac). Most hypogene minerals on the earth’s surface are unstable and break down, becoming supergene minerals under the influence of weathering processes.