Hydrated Silica
Most valuable. Ranges from grey to black. Unusual darkness of the stone comes from carbon and iron oxide trace elements. Most Black opals have a natural layer of colorless opal left on the back of the stone. The darker the backing, the greater vibrancy of color and higher value. Black Opal has been said to shield against negative energy and stimulate creativity.
Northern Ethiopia
Length/Depth: 0.13 in
Width: 0.75 in
Height: 1.25 in