A variety of chalcedony quartz that is a very common and used often in jewelry. When chalcedony is variegated with with spots or figures, or arranged in differently colored layers, it is called agate; and if by reason of the thickness, color, and arrangement of the layers it is suitable for being carved into cameos, it is called onyx. It comes in a wide range of colors including black, gray, brown, red, green, pink, blue, white, and yellow. Agate can be flecked with color, such as Moss Agate and Tree Agate, and is often banded, exhibiting layers of quartz crystals. Agate is often dyed to enhance the color and banding. There are a variety of popular agates including onyx, Eye Agate, Blue Lace Agate, Moss Agate, Tree Agate, and White Agate. (See individual listings)