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Natural Spinel Gemstone Information
Chemical Composition and Properties
The word spinel either comes from a Greek word ‘spinther’ meaning ‘spark’ or from a Latin word ‘spina’ meaning ‘thorn’. The chemical formula of the genuine spinel is MgO Al2 O3 / manganesium aluminium oxide. The refractive index ranges between 1.712 and 1.80 and its specific gravity is 3.58 to 3.64. The hardness of this stone according to Mohs scale of hardness is 8. The gemstone is flawless, clear and transparent. Tiny small inclusions might be seen only after adequate magnification. Spinel is stable to light and chemicals, but avoid high heat as it may cause the color to fade.
This common metamorphic mineral occurs in metamorphosed limestones and crystalline schists, serpentines and gneisses. Also found in contact metamorphosed crystalline limestones and rocks poor in silica where it is associated with calcite. The stone has been described as an alteration product of garnet and corundum. It is also an igneous rock’s primary component and a product of metamorphism in rocks that is rich in magnesium. Found frequently in stream sands as rolled pebbles, where it has been preserved on account of its chemical durability and hardness.
Colors and Treatments
This stone is found in many different colors ranging from red, violet, purple, pink, green and indigo to blue. The deep red is the most valuable and popular color. The red spinel in ancient times was often mistaken for an actual natural ruby and it was only on close inspection that once could tell the difference. The color change varieties and star spinels are also found but they are not easily available. Normally spinel is faceted in an oval cut used for fashion jewelry like earrings, rings and the like. Since many spinels are completely clean and devoid of flaws, they are mostly untreated. Clean the stone with mild soap and use soft toothbrush to scrub behind the gemstone where dust can collect. Steam and ultrasonic cleaning are usually safe.
Famous Spinels and Simulants
Some of the world’s most illustrious “rubies” are actually spinels. The Black Prince’s Ruby, which is a part of British Crown jewels is actually a spinel. The 350 carats Timur Ruby that graces the front of Imperial State Crown of England is also a spinel. Synthetic spinel, tourmaline, cobalt glass, zircon, aquamarine, ruby, sapphire and garnet are the common simulants of the natural spinel. Spinel can distinguished easiy from other minerals by its hardness (8), its vitreous luster and its octahedral crystals. Gem-quality material is typically transparent and faceted, but to find sizes larger than 5 cts is very hard.
Where Spinels are Found
Spinels are mined in Brazil, Australia, Burma (Myanmar), India, Afghanistan, Thailand, Sri Lanka (previously called Ceylon), Sweden and The United States. Spinels with best quality are found in the burmese mines. Spinel is found as a metamorphic mineral and also as primary mineral in mafic igneous rocks; in those igneous rocks, the magmas are relativly deficient in alkalis relative to aluminium, and alumunium oxide may form as mineral corundum or may form spinel when combined with magnesia. This is why ruby and spinel are often found together.
Healing and Metaphysical Properties
Spinel is thought to protect its wearer from harm, to reconcile differences and to soothe away sadness. It helps to improve physical vitality and appearance and can be used to enhance energy during physical activity. In terms of metaphysical properties, the stones have a calm and subdued effect. Pink Spinel offers gentle energy renewal, and is very helpful for those who suffer from chronic conditions and fatigue. It is used also as a talisman to carry the love of the giver. That makes this pink spinel a wonderful stone for long-distance relationships or times when couples cannot be together physically.