alexandrite vs chrysoberyl

alexandrite and chrysoberyl both are nouns.

Word	Noun	Adjective	Verb	Adverb
alexandrite	Yes	No	No	No
chrysoberyl	Yes	No	No	No

As nouns, chrysoberyl is a hypernym of alexandrite; that is, chrysoberyl is a word with a broader meaning than alexandrite:

alexandrite: a green variety of chrysoberyl used as a gemstone
chrysoberyl: a rare hard yellow green mineral consisting of beryllium aluminate in crystal form; used as a gemstone

alexandrite (noun)	chrysoberyl (noun)
a green variety of chrysoberyl used as a gemstone	a rare hard yellow green mineral consisting of beryllium aluminate in crystal form; used as a gemstone