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A granular hypabyssal rock composed principally of calcic plagioclase, augite, and sometimes hornblende, with some brotite and analcime.



(from Teschen, the German name for the Polish city of Cieszyn), a plutonic rock; one of the alkalic gabbroids. Teschenite consists of basic plagioclase, augite, and analcime; it can also contain hornblende, other zeolites, and such accessory minerals as apatite and magnetite. The rock, whose texture is diabasic, forms small hypabyssal masses, dikes, and sills.

In the USSR, teschenite can be found in the Caucasus and in Southern Siberia (Minusinsk Basin). Teschenite is a beautiful ornamental stone.