Plagioclase

Pronunciation

• UK IPA: /ˈpleɪdʒɪəkleɪz/
• US IPA: /ˈplædʒɪəkleɪz/

Origin

From - + clase + -, after German Plagioklas.

Full definition of plagioclase

Noun

1. (mineralogy) Any of a group of aluminum silicate feldspathic minerals ranging in their ratio of calcium to sodium.
• 2004, Richard Fortey, The Earth, Folio Society 2011, p. 51:These crystals are of one of the most abundant minerals in nature – feldspar; furthermore, they are of a particular kind of feldspar rich in the element calcium, termed plagioclase.