HYALITE

Dictionary of Science, Literature and Art · 1842 · p. 22

(Yunanca köken — orijinale bakınız.) A yellow or grey variety of uncleavable quartz or opal; it is commonly concretionary or chalcedonic, ofa vitreous fracture and lustre. It occurs in trap rocks in grains, filaments, and rhomboidal ma es: it is silica combined with about 6 per cent, of water. [s. 581]