Black spinel

Black spinel is the opaque jet-black variety of spinel. Black spinel is the premier black gemstone. With a hardness of 8, it's extremely durable. Black spinel lacks the metallic lustre of hematite or black diamond, other popular black gemstones.

Summer 1971, Black spinel (high R.I. and hardness), p. 318, 1p.
Fall 1971, Synthetic spinel and strontium titanate doublets, p. 346, 4pp.
Fall 1971, Synthetic red spinel, p. 350, 2pp.

Rockhounding helps gemologists and mineralogists hunt and discover minerals and precious gemstones like jasper, opal, agate, turquoise, geodes, zircon, black spinel, garnet, varieties of quartz, topaz and tourmaline and so on.

Black spinel, by the way, makes a less expensive substitute for black diamond and a more durable, if more expensive, alternate for black onyx.

The best blue and violet spinels are found in Sri Lanka (Ceylon). Gem spinel is also found in Vietnam, the Pamir mountains of Tajikistan, Tanzania and Madagascar. Black spinel is mined in Thailand (at Bo Ploi, Kanchanaburi).

See also: Spinel, Stone, Gemstone, Gemstones, Jewel