nepheline vs nephelite

nepheline and nephelite both are nouns.

Word	Noun	Adjective	Verb	Adverb
nepheline	Yes	No	No	No
nephelite	Yes	No	No	No

As nouns, nepheline and nephelite are synonyms defined as:

nepheline and nephelite: a whitish mineral consisting of sodium aluminum silicate or potassium aluminum silicate in crystalline form; used in the manufacture of ceramics and enamels

nepheline (noun)	nephelite (noun)
a whitish mineral consisting of sodium aluminum silicate or potassium aluminum silicate in crystalline form; used in the manufacture of ceramics and enamels	a whitish mineral consisting of sodium aluminum silicate or potassium aluminum silicate in crystalline form; used in the manufacture of ceramics and enamels