- quartz glass, quartz, vitreous silica, lechatelierite, crystal - colorless glass made of almost pure silica
--1 is a kind of natural glass
- quartz - a hard glossy mineral consisting of silicon dioxide in crystal form; present in most rocks (especially sandstone and granite); yellow sand is quartz with iron oxide impurities
--2 is a kind of mineral
--2 has substances:
--2 has particulars:silicon, Si, atomic number 14; silica, silicon oxide, silicon dioxide quartz crystal; rock crystal, transparent quartz; cairngorm, smoky quartz; amethyst; chalcedony, calcedony; citrine; rose quartz; sunstone, aventurine; topaz, false topaz, common topaz