Gemology 101

Gemstones equal millions of years of history. They begin as carbon in the mantle of the earth, then as discoveries among the rubble of the earth's crust and finally, as physical evidence of the many lives and the earth's forces that have touched each stone. 

Each stone tells its individual story by the inclusions that, for a gemologist, are fascinating. For example, a ruby might contain certain mineral inclusions only found in Mynanmar thus, helping the gemologist to clearly identify the source country of the stone. The deep pigeon blood red body color that glow with red fluorescence and light-scattering inclusions scream "we're from Mgok, Myanmar." Emeralds from Colombia also have color markers that are a geographical marker for their origin. The same can be said about sapphires that come from Myanmar versus those that originate in Montana. Inclusions can be either a specific figure, mineral or a color.

Colombian emeralds have some other identifying characteristics that for gemologists, indicate that the stone is from Colombia and not from Afghanistan, another source. A Trapiche emerald from one of two Muzo Colombian mines can only be from Colombia because of their six rays that form a wheel pattern.  These rays emanate from  a hexagonal shaped center.  In contrast, Brazilian emeralds are bluer than their Colombian counterparts because of the increased presence of iron. 

Since January is the month of garnets, here are some of the countries from where they are sourced: the USA, Tanzania, Kenya, Brazil, Iran, Thailand, Afghanistan and Russia. Speaking of colors, garnets come in a rainbow; red, orange, yellow, green, blue, purple, pink, brown, black and colorless with reddish shades most common.  One very unique inclusion in a garnet is the curving, radiating bundles of fibers known as a horsetail figure specific to demantoid garnets. Yes, it really looks like a horsetail and yes, this very unique inclusion will confirm the garnet is a demantoid from Russia or Afghanistan and not say, a Colombian emerald or any other garnet.

The world of gemology and gemstones is fascinating and replete with great stories of discovery, adventure and knowledge about the planet.  Stay tuned for another blog piece about a gemstone that has cultivated great interest; tourmalines. Like garnets, tourmalines come in all colors.   Yet, the Paraiba, tourmaline is one with a very special provenance and color palette.   



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