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Mineralati

Minerals

Orthoclase

orthoclase

K(AlSi3O8)

orthoclase orthoclase feldspar mineral stone 19958416 Stock Photo at ...

orthoclase orthoclase feldspar mineral stone 19958416 Stock Photo at ... — via www.vecteezy.com · Source

Overview

Orthoclase, or orthoclase feldspar (endmember formula KAlSi3O8), is an important tectosilicate mineral which forms igneous rock. The name is from the Ancient Greek for "straight fracture", because its two cleavage planes are at right angles to each other. It is a type of alkali feldspar, also known as potassium feldspar or K-spar. The gem known as moonstone (see below) is largely composed of orthoclase.

Identification characteristics

  • Mohs hardness 6

Scientific references

  1. Orthoclase — Wikidata. https://www.wikidata.org/wiki/Q21813710 Link
  2. Orthoclase — Wikipedia. https://en.wikipedia.org/wiki/Orthoclase Link