collectible vs curio

collectible and curio both are nouns.

Word	Noun	Adjective	Verb	Adverb
collectible	Yes	Yes	No	No
curio	Yes	No	No	No

As nouns, curio is a hypernym of collectible; that is, curio is a word with a broader meaning than collectible:

collectible: things considered to be worth collecting (not necessarily valuable or antique)
curio: something unusual -- perhaps worthy of collecting

Other hypernyms of collectible include curiosity, oddity, oddment, peculiarity, rarity.

collectible (noun)	curio (noun)
things considered to be worth collecting (not necessarily valuable or antique)	something unusual -- perhaps worthy of collecting

collectible (adjective)	curio (adjective)
subject to or requiring payment especially as specified