Sixteen Spinel facts
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| Red Spinel |
- The origin of the name spinel is unknown. It may be a derivative of the Latin word «spinella» or from a Greek word meaning spark, in reference to the bright red or orange color of some crystals.
- Spinel is the magnesium aluminum member of the larger spinel group of minerals. It has the formula MgAl2O4.
- Many famous rubies in crown jewels are in fact spinel.
- In the past, before the arrival of modern science, spinels and rubies were equally known as rubies. After the 18th century the word ruby was only used for the red gem variety of the mineral corundum and the word spinel became used.
- A faceted red spinel of more than 400 carats belonged to Empress Catherine II of Russia, and is now part of the Russian Treasure in the Kremlin.
- True spinel has long been found in the gemstone-bearing gravel of Sri Lanka and in limestones of the Badakshan Province in nowadays Afghanistan and of Mogok in Burma.
- One of the most fascinating gemstone in the world is the «Timur ruby» which is a red spinel weighting 361 carats, that is cut in cabochon and named after Tamerlain, the Tartar conqueror, who was one of his owners.
- This stone has the names of its former owners engraved upon it, and some of them are the same with previous owners of the famous Kohinoor diamond.
- The Tamerlain is now owned by Queen Elizabeth of England.
- Another famous historical spinel set in the British Crown Jewels is the «Black Prince's Ruby». This cabochon of an estimated weight of 170 carats, was worn on the battle helmet of Henry V during the battle of Azincourt in 1415.
- Spinel, (Mg,Fe)Al2O4, is a common mineral in the Ca-Al-rich inclusions in some chondritic meteorites.
- Spinel owns his color to chromium, for the red to orange stones, to manganese for the violet and to iron for the blue variety.
- Mohs scale hardness: 7.5 – 8.0
- Spinels were most often referred to as «balas rubies», name which may have referred to their country of origin, either Badakshan in Afghanistan or the Balaksh region of Sri Lanka.
- Another extremely rare variety is the attractive cobalt blue spinel, seen only in small sizes in some mineral collections.
- Occasionally, a color changing variety called « alexandrite like spinel » can be found; its color turns from a light gray blue in daylight to a light purple under artificial light.
