vitreous silica vs crystal

vitreous silica and crystal both are nouns.

Word	Noun	Adjective	Verb	Adverb
vitreous silica	Yes	No	No	No
crystal	Yes	No	No	No

As nouns, vitreous silica and crystal are synonyms defined as:

Other synonyms of vitreous silica include lechatelierite, quartz, quartz glass.

vitreous silica (noun)	crystal (noun)
colorless glass made of almost pure silica	a protective cover that protects the face of a watch
	glassware made of quartz
	a crystalline element used as a component in various electronic devices
	a rock formed by the solidification of a substance; has regularly repeating internal structure; external plane faces
	a solid formed by the solidification of a chemical and having a highly regular atomic structure
	colorless glass made of almost pure silica