All natural untreated orange Spessartine Garnet Stone from Afghanistan.

-- 3 pieces Lot Oval shape cabochon

Weight: 75 carat (15 gram) in total

Dimension:  20x15x8 mm, 21x13x8 mm, 21x15x7 mm

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Spessartine (spessartite) Garnet

Spessartine or spessartite is a nesosilicate, manganese aluminium garnet species, Mn2+3Al2(SiO4)3.

The name is a derivative of Spessart in Bavaria, Germany, the type locality of the mineral. It occurs most often in granite pegmatite and allied rock types and in certain low-grade metamorphic phyllites. Sources include Australia, Myanmar, India, Sri Lanka, Afghanistan, China, Israel, Madagascar, Tanzania, Namibia and the United States. Spessartine of an orange-yellow has been called Mandarin garnet and is found in Madagascar. Violet-red spessartines are found in rhyolites in Colorado and Maine. In Madagascar, spessartines are exploited either in their bedrock or in alluvium. The orange garnets result from sodium-rich pegmatites. Spessartines are found in bedrock in the highlands in the Sahatany valley. Those in alluvium are generally found in southern Madagascar or in the Maevatanana region.

Spessartine forms a solid solution series with the garnet species almandine. Well-formed crystals from this series, varying in color from very dark-red to bright yellow-orange, were found in Latinka, Rhodope Mountains, Kardzhali Province, Bulgaria. Spessartine, like the other garnets, always occurs as a blend with other species. Gems with high spessartite content tend toward a light orange hue, while almandine prevalence induces red or brownish hues.

The mineral spessartite should not be confused with a type of igneous rock, which is also called spessartite.

Spessartite garnet can be identified by its orange colour. Garnet in general can be distingushed from other gem types by its occurrence in metamorphic rock, its hardness (6.5 - 7.5 on the Mohs scale), colour, refractive index and cubic crystal structure. However, the quickest way to identify garnet is with the use of strong neodymium magnets. Garnet is attracted to neodymium magnets because it contains high concentrations of iron and/or manganese. Spessartite garnet can be distinguished from other garnet types by its high range of magnetic susceptibility (SI).

The most desirable gemstones come from Namibia and are known as "mandarin spessartite".

Spessartite garnet can range in colour from warm yellow to orange-red. The most desired colour for spessartite garnet is a reddish-orange, which is known as "aurora red" or "mandarin spessartite". This is a pure orange without brown tints.

Spessartite garnet's high refractive index and vitreous lustre means that it has good brilliance. Spessartite garnet is transparent to translucent. "Eye clean" gemstones are quite rare for this variety of garnet.

Translucent spessartite garnet is commonly cut en cabochon and transparent material is cut in a variety of faceted shapes.

Spessartite garnet is not known to be treated or enhanced in any way.