Agate

Agate is rock made of layers of quartz. These layers, when the stone is cut, often show as rings, sometimes of different colors.

Agate usually occurs as rounded lumps or veins. Agates can be made up from a lot of different kinds of quartz, and sometimes chalcedony, carnelian, amethyst, jasper, and opalshow up as layers in agate.

Agate is often used for ornamentals. Different kinds of agate have names like star agate, clouded agate, and moss agate.