The name "spinel" is derived from the Greek word for spark, in reference to the fiery red color of spinels often used for gems. Spinel is found in virtually all the colors due to the impurities present in it, which are responsible for a particular color in spinel. The most popular variety of spinel is red which is colored by chromium and iron. Red spinel for many years was considered as a variety of ruby. Blue spinel is colored by iron and rarely by cobalt. Star stones are rare in tourmaline but can show 4-rayed or 6-rayed star when spinel is cut as a cabochon.

Locations:

Spinel is mainly found in Sri Lanka, Burma and Madagascar. Some other locations where spinel is found are Pakistan, Afghanistan, Australia, Brazil, Sweden, Turkey, Italy, USA and the former USSR.

Chemical Composition: Magnesium Aluminum Oxide
Crystal Structure: Cubic
Hardness: 8
Specific Gravity: 3.60
Refractive Index: 1.71-1.73
Colors: Red, pink, violet, yellow, orange, blue, dark green and black.
Luster: Vitreous

Astrological Relevance:

Spinel is considered as one of the birthstones for the zodiac sign of Capricorn (December 21 To January 21).