This red colour reflects the level of chromium and iron deposits in the gem's composition. In different amounts, these chemicals can create any colour from a light rose to a deep red.
So vibrant are the deep red examples of spinel that it was once considered a form of ruby and, for many years, it was difficult to differentiate between the two.
Spinel is commonly found in many countries, including Afghanistan, Sweden, Brazil, Kenya, Nigeria, Tanzania, Pakistan, Tajikistan, Thailand, Vietnam and Australia.
The illustrious red spinel is a product of Burma, while the deep blue and purple examples are customary of high-quality stones in Sri Lanka.
While the most precious gems are deep red, the purest types of spinel are actually white.
Spinel can also be found in burnt orange, rich blue to violet hues (characteristic of examples mined in Asia), green (so dark that it is almost black), and in colourless forms.
The extensive palette of colours is due to how easily the stone is manipulated by chemical impurities. This attribute has made the gem extremely susceptible to artificial manufacture and labs regularly generate spectacular colours by adding different chemicals. As a result, synthetic spinel is often used to mimick birthstones, a role that has damaged the integrity of the gem.
Its reputation as a great imposter is further enhanced by the fact that many of the world's most famous rubies have actually proven to be natural spinel. Indeed, at one stage, spinel was even known as Balas Ruby.
Folklore entails that Balas rubies would afford the wearer protection from financial and physical ruin. In some cases, the gem has been said to improve mental powers, expanding the imagination and controlling the thoughts of others.
Perhaps the largest of these mistaken gems is the 170-carat Black Prince ruby that travelled from Morocco to Spain, until it was ultimately set into the Imperial State Crown in the British Crown Jewels. Ironically, fine spinel is now rarer than the ruby it has been used to replicate.
The origin of the word 'spinel' is unknown; however, it is most likely to have evolved from the Latin ‘spinella’, which means 'little thorn'. This may be a reference to the sharp points that appear on most spinel crystals.
Alternatively, and given the popularity of its ruby-like redness, a possible derivation exists from the Greek term for 'spark'.
While spinel is comparatively hard, rating an 8 on the Mohs scale, it tends to be brittle by nature and is therefore best used as a decorative gem in jewellery. It is most often faceted in oval, round or cushion shapes, and is not currently found in calibrated sizes.
Now treasured for its own sake, spinel is a favourite among gem collectors due to its brilliance, hardness and wide range of spectacular colours.
Fact Sheet
February - Spinel
Hardness: 8
Variety of: Aluminate of magnesium
Found: Burma, Sri Lanka, Africa, Australia, Pakistan, Sweden and Brazil
birthstones
Modern birthstone - Amethyst
Traditional birthstone - Amethyst
Mystical birthstone - Bloodstone
Ayurvedic birthstone - Amethyst
Zodiac birthstones
Aquarius (January 20 - February 18) Garnet, Moss Agate, Opal, Amethyst
Pisces (February 19 - March 20) Rock Crystal, Sapphire, Amethyst, Bloodstone