a variety of microcline, rich in sodium and sometimes having a play of color: sometimes considered a variety of orthoclase.
Origin of anorthoclase
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
A white to colorless triclinic mineral of the alkali feldspar group. It is a common constituent in the matrices of slightly alkaline volcanic rocks. Chemical formula: (Na,K)AlSi3O8.
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