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.
Origin of sanidine
1805–15;Related formssan·i·din·ic [san-i-din-ik] /ˌsæn ɪˈdɪn ɪk/, adjective
< German Sanidin,
equivalent to Greek sanid-
(stem of sanís
plank) + German -in -ine2
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Examples from the Web for sanidine
Historical Examples of sanidine
All the upper part of the mountain is composed of a pumiceous tufa, rich in sanidine and of a characteristic greenish colour.
They are rich in leucite, but contain also some sanidine and often much nepheline with hauyne or nosean.
They are of trachytic appearance, containing phenocysts of sanidine, leucite, augite and biotite.
Sanidine, san′i-din, n. a clear glassy variety of orthoclase.
It is remarkable for the large crystals of sanidine (glassy felspar) which it contains, and has a rude columnar structure.
British Dictionary definitions for sanidine
an alkali feldspar that is a high-temperature glassy form of orthoclase in flat, tabular crystals, found in lavas and dykes. Formula: KAlSi 3 O 8
Word Origin for sanidine
C19: from German, from Greek sanis, sanidos a board
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
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