silica vs chert

silica and chert both are nouns.

Word	Noun	Adjective	Verb	Adverb
silica	Yes	No	No	No
chert	Yes	No	No	No

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

silica: a white or colorless vitreous insoluble solid (SiO2); various forms occur widely in the earth's crust as quartz or cristobalite or tridymite or lechatelierite
chert: variety of silica containing microcrystalline quartz

Other hyponyms of silica include flint, silex.

silica (noun)	chert (noun)
a white or colorless vitreous insoluble solid (SiO2); various forms occur widely in the earth's crust as quartz or cristobalite or tridymite or lechatelierite	variety of silica containing microcrystalline quartz