Description
this is from thailand 100% Satisfaction Guaranteed Delivery Time 14-21 Days Quantity 1 Piece Gemstone: Spinel Size: 19x14.8x5 mm Original Myanmar Spinel (/spəˈnɛl, ˈspɪnəl/) is the magnesium/aluminium member of the larger spinel group of minerals. It has the formula MgAl 2O 4 in the cubic crystal system. Its name comes from the Latin word spinella, which means spine in reference to its pointed crystals.[4] Spinel crystallizes in the isometric system; common crystal forms are octahedra, usually twinned. It has no true cleavage, but shows an octahedral parting & a conchoidal fracture.[6] Its hardness is 8, its specific gravity is 3.5-4.1, & it is transparent to opaque with a vitreous to dull luster. It may be colorless, but is usually various shades of red, lavender, blue, green, brown, black, or yellow[7] Some spinels are among the most famous gemstones; among them are the Black Prince's Ruby & the "Timur ruby" in the British Crown Jewels,[8] & the "Côte de Bretagne", formerly from the French Crown jewels.[9] The Samarian Spinel is the largest known spinel in the world, weighing 500 carats (100 g).[10] The transparent red spinels were called spinel-rubies[11] or balas rubies.[12] in the past, before the arrival of modern science, spinels & 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 & the word spinel came to be used.[13] "Balas" is derived from Balascia, the ancient name for Badakhshan, a region in central Asia situated in the upper valley of the Panj River, one of the principal tributaries of the Oxus River. However, "Balascia" itself may be derived from Sanskrit bālasūryaka, which translates as "crimson-coloured morning sun".[14] Mines in the Gorno Badakhshan region of Tajikistan constituted for centuries the main source for red & pink spinels.[13] Free delivery by Thailand Post. Delivery time 14-21 business days. I also offer delivery via DHL, delivery time 3-5 business days, for this you need to buy DHL delivery on my list. If you purchase more than 300 US, DHL delivery will be free. 15.10 Carats Natural Pink Spinel Burmese | Untreated
