opal vs girasol

opal and girasol both are nouns.

Word	Noun	Adjective	Verb	Adverb
opal	Yes	No	No	No
girasol	Yes	No	No	No

As nouns, girasol is a hyponym of opal; that is, girasol is a word with a more specific, narrower meaning than opal:

opal: a translucent mineral consisting of hydrated silica of variable color; some varieties are used as gemstones
girasol: an opal with flaming orange and yellow and red colors

Other hyponyms of opal include black opal, fire opal, harlequin opal.

opal (noun)	girasol (noun)
a translucent mineral consisting of hydrated silica of variable color; some varieties are used as gemstones	tall perennial with hairy stems and leaves; widely cultivated for its large irregular edible tubers
	an opal with flaming orange and yellow and red colors