chert vs silica

chert and silica both are nouns.

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

As nouns, silica is a hypernym of chert; that is, silica is a word with a broader meaning than chert:

chert: variety of silica containing microcrystalline quartz
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

Other hypernyms of chert include silicon dioxide, silicon oxide.

chert (noun)	silica (noun)
variety of silica containing microcrystalline quartz	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