- an opaque, brown glass containing fine, gold-colored particles.
- any of several varieties of minerals, especially quartz or feldspar, spangled with bright particles of mica, hematite, or other minerals.
- a dark-coloured glass, usually green or brown, spangled with fine particles of gold, copper, or some other metal
- a light-coloured translucent variety of orthoclase feldspar containing reddish-gold particles of iron compounds
- a variety of quartz containing red or greenish particles of iron oxide or mica: a gemstone
