beryl vs emerald

beryl and emerald both are nouns.

Word	Noun	Adjective	Verb	Adverb
beryl	Yes	No	No	No
emerald	Yes	No	No	No

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

beryl: the chief source of beryllium; colored transparent varieties are valued as gems
emerald: a green transparent form of beryl; highly valued as a gemstone

Other hyponyms of beryl include aquamarine, morganite.

beryl (noun)	emerald (noun)
the chief source of beryllium; colored transparent varieties are valued as gems	the green color of an emerald
	a transparent piece of emerald that has been cut and polished and is valued as a precious gem
	a green transparent form of beryl; highly valued as a gemstone