Colorless glass made of almost pure silica.

synonyms: crystal, lechatelierite, quartz glass, vitreous silica.

Roget 323: hardness etc. adj.; rigidity; renitence^†, renitency; inflexibility, temper, callosity, durity^†.    induration, petrifaction; lapidification^†, lapidescence^†; vitrification, ossification; crystallization.    stone, pebble, flint, marble, rock, fossil, crag, crystal, quartz, granite, adamant; bone, cartilage; hardware; heart of oak, block, board, deal board; iron, steel; cast iron, decarbonized iron, wrought iron; nail; brick, concrete; cement.    ... show more

Dutch: kwartsglas
Polish: kryształ, kryształ górski

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.

Dutch: kwarts
Polish: kwarc