MINERAL OF THE QUARTER By Ronald L. Parker Senior Geologist, Borehole Image Specialists, 5650 Greenwood Plaza Boulevard, Suite 142, Greenwood Village, CO 80111 | ron@bhigeo.com
CASSITERITE Catalyst of Human Technological Advance
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Spray of lustrous, brown-black cassiterite crystals scattered across euhedral faces of a large translucent smoky quartz crystal from Tenkerchin Mine, Chukotka, Magadan Oblast, Russia. Some of these cassiterites show tetragonal symmetry which is often obscured by twinning in other crystals. Used with permission from John Betts Fine Minerals. www.johnbetts-fineminerals.com OUTCROP | January 2019
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Vol. 68, No. 1 | www.rmag.org