quartz has definitions from the fields of geology,chemistry
1
[ noun ] (chemistry) colorless glass made of almost pure silica

Used in print

(Walter H. Buchsbaum, "Advances in Medical Electronics"...)

The microscope and orthicon are both selected to operate well into the ultraviolet_spectrum , which means that all lenses must be quartz .

2
[ noun ] (geology) 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
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