Spinel Designs
Spinel
crystallizes in the isometric system; common crystal forms are octahedra,
usually twinned. It has an imperfect octahedral cleavage and a conchoidal
fracture. Its hardness is 8, its specific gravity is 3.5-4.1 and it is
transparent to opaque with a vitreous to dull lustre. It may be colorless, but
is usually various shades of red, blue, green, yellow, brown or black. There is
a unique natural white spinel, now lost, that surfaced briefly in what is now
Sri Lanka. Some spinels are among the most famous gemstones: Among them is the
Black Prince's Ruby and the 'Timur ruby' in the British Crown Jewels, and the
'cote de Bretagne' formerly from the French Crown jewels. The Samarian Spinel is
the largest known 500 carat spinel in the world.
The transparent red spinels were called spinel-rubies or balas-rubies. In the
past, before the arrival of modern science, spinels and rubies were equaly known
as rubies. After the XVIII the word ruby was only used for the red gem variety
of the mineral corundum and the word spinel became used. "Balas" is derived from
Balascia, the ancient name for Badakhshan, a region in central Asia situated in
the upper valley of the Kokcha river, one of the principal tributaries of the
Oxus river. The Badakshan province was for centuries the main source for red and
pink spinels.
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EXAMPLE ONLY
Private Collection
Other Stones Available |
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EXAMPLE ONLY
Private Collection
Other Stones Available
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