Ironflint

I'RONFLINT, n. Ferruginous quartz; a subspecies of quartz, opake or translucent at the edges, with a fracture more or less conchoidal, shining and nearly vitreous. It is sometimes in very minute and perfect six-sided prisms, terminated at both extremities by six-sides pyramids. It occurs also in masses, and in small grains. Its varieties are red, yellow,and greenish.