plagioclase vs oligoclase

plagioclase and oligoclase both are nouns.

Word	Noun	Adjective	Verb	Adverb
plagioclase	Yes	No	No	No
oligoclase	Yes	No	No	No

As nouns, plagioclase and oligoclase are synonyms defined as:

plagioclase and oligoclase: any of a series of triclinic feldspars that form rocks

plagioclase (noun)	oligoclase (noun)
any of a series of triclinic feldspars that form rocks	any of a series of triclinic feldspars that form rocks