dolomite vs bitter spar

dolomite and bitter spar both are nouns.

Word	Noun	Adjective	Verb	Adverb
dolomite	Yes	No	No	No
bitter spar	Yes	No	No	No

As nouns, dolomite and bitter spar are synonyms defined as:

dolomite and bitter spar: a light colored mineral consisting of calcium magnesium carbonate; a source of magnesium; used as a ceramic and as fertilizer

dolomite (noun)	bitter spar (noun)
a kind of sedimentary rock resembling marble or limestone but rich in magnesium carbonate	a light colored mineral consisting of calcium magnesium carbonate; a source of magnesium; used as a ceramic and as fertilizer
a light colored mineral consisting of calcium magnesium carbonate; a source of magnesium; used as a ceramic and as fertilizer