Standard Lemma guide

oligoclase

noun · 2 senses · updated from the 2026-07-25 local source snapshot

Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.

Sound

Pronunciation

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1

noun

Meaning 1

A plagioclase feldspar, the second member of the Albite-Anorthite solid solution series. Primarily found as small crystals in impure marble. Oligoclase contains a small amount of calcium substituting for some of the sodium in its formula. Oligoclase with reddish-golden inclusions found in Norway and Canada is called sunstone.

Definition source: English Wiktionary via Wiktextract

Usage: uncountable, usually

Topics: chemistry, geography, geology, mineralogy, natural-sciences, physical-sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

2

noun

Meaning 2

any of a series of triclinic feldspars that form rocks

Definition source: Princeton WordNet 3.0

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: plagioclase

Antonyms: none provided

Broader terms: feldspar, felspar

Narrower terms: albite, white feldspar, anorthite

History

Etymology

From oligo- + -clase.