Mineralogy Photography

Cassiterite

 

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tanbuľka

Name origins: 

The name derives from the Greek “kassiteros” meaning tin, or from “Cassiterides” , a name of islands off the western coast of Europe in pre-Roman time.

Description:

Cassiterite is a main ore of tin, sometimes named as tinstone,forms short prismatic or dipyramidal crystals. This mineral also occurs in granular, earthy, or kidney form. It is ussually brown or black, sometimes yellowish or colourless. cassiterite has white, grey or brownish streak. It is hard and heavy, partially transparent or almost opaque, with diamond luster on its crystal surfaces. It is greasy on freshly broken areas. It has poor cleavage and subchonchoidal fracture.  Commercially important quantities occur in placer deposits, high temperature hydrotermal weins and pegmatites associated with granitic intrusives. It is also a widespread minor constituent of igneous rocks. Today most of the world’s cassiterite is mined in  Bolivia, Malaysia, Indonesia, Nigeria, Myanmar (Burma), Thailand, and parts of China. The specimen shown below contains two crystals of cassiterite surrounded by the crystals of muscovite on leucogranite matrix. The sample comes from Iuľtin mine, Tschukotka, Russia. In Iuľtin, there is a quartz vein-type tin-tungsten deposit, located in the exo- and endocontact of a leucogranite stock.

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