[san-i-deen, -din]
noun Mineralogy.
a glassy, often transparent variety of orthoclase in which sodium may replace as much as 50 percent of the potassium: forms phenocrysts in some igneous rocks.

1805–15; < German Sanidin, equivalent to Greek sanid- (stem of sanís plank) + German -in -ine2

sanidinic [san-i-din-ik] , adjective Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
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World English Dictionary
sanidine (ˈsænɪˌdiːn, -dɪn)
an alkali feldspar that is a high-temperature glassy form of orthoclase in flat, tabular crystals, found in lavas and dykes. Formula: KAlSi3O8
[C19: from German, from Greek sanis, sanidos a board]

Collins English Dictionary - Complete & Unabridged 10th Edition
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Encyclopedia Britannica


alkali feldspar mineral, a high-temperature form of potassium aluminosilicate (KAlSi3O8) that sometimes occurs in surface rocks. Sanidine forms colourless or white, glassy, transparent crystals in acidic volcanic rocks.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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Select all extrusive igneous rock units that contain sanidine.
Display all extrusive igneous rock units that contain sanidine.
Show me all extrusive igneous rock units that contain sanidine.
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