sanidine

[ san-i-deen, -din ]

noun

, Mineralogy.

1. 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.

sanidine

/ ˈsænɪˌdiːn; -dɪn /

noun

1. 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

Other Words From

• san·i·din·ic [san-i-, din, -ik], adjective

Word History and Origins

Origin of sanidine¹

1805–15; < German Sanidin, equivalent to Greek sanid- (stem of sanís plank) + German -in -ine ²

Word History and Origins

Origin of sanidine¹

C19: from German, from Greek sanis, sanidos a board

Example Sentences

All the upper part of the mountain is composed of a pumiceous tufa, rich in sanidine and of a characteristic greenish colour.

From Project Gutenberg

Sanidine, san′i-din, n. a clear glassy variety of orthoclase.

From Project Gutenberg

It is remarkable for the large crystals of sanidine (glassy felspar) which it contains, and has a rude columnar structure.

From Project Gutenberg

(c.) Phonolite (Clinkstone) is a trachytic rock, composed essentially of sanidine, nepheline, and augite or hornblende.

From Project Gutenberg

Trachyte from Hungary; felsitic paste with crystals of hornblende and sanidine, and a little magnetite.

From Project Gutenberg