No. I know what you’re thinking. Garnets: wine colored, dull semi-precious stones. Poor man’s Ruby. Well guess what, you don’t know a thing about garnets then. Garnet is not a single mineral, but a group contains closely related, isomorphous minerals that form a series with each other. The Garnets vary only slightly in physical properties, and some of the members may be so similar that they are indistinguishable from one another without x-ray analysis.

Garnet 2

From a mineralogical standpoint there‚Äôs like 20 different species of garnets, garnets that fall somewhere inbetween those species, and then color variations within those that lead to different semi-official classifications. It’s a delightful clusterfuck of color and chemicals. But ain’t nobody got time for that, so for simplicity’s sake, I’m going to condense it to 6 basic types of garnets.

Almandine

Almandine AKA: Carbuncle, Oriental garnet, Syrian Garnet, Ceylon Ruby.

This is pretty standard dark red/purplish garnet. Chemically, almandine is an iron-aluminum garnet. Nothing to write home about.

Pyrope

Pyrope

This is the lazy garnet. Pretty much only comes in red, unlike the other varieties which took it upon themselves to show some initiative and branch out. It’s really similar to Almandine but tends to be clearer, making it preferable as a cut gem. Pyrope is sometimes found with Diamonds. It is an aluminum silicate. Pyrope has trade names some of which are misnomers; Cape ruby, Arizona ruby, California ruby, Rocky Mountain ruby, and Bohemian garnet from the Czech Republic. Another intriguing find is the blue color-changing garnets from Madagascar, a pyrope-spessartine mix. The color of these blue garnets is not like sapphire blue in subdued daylight but more reminiscent of the grayish blues and greenish blues sometimes seen in spinel.

Spessartine

Spessartine

AKA: Mandarin Garnet, Spessartite.

Found all over the world but not China, so I have no clue why people call it Mandarin Garnet sometimes. Also comes in pinks, purples, and reds. Spessartine is manganese aluminum garnet.


Uvarovite

Uvarovite

Uvarovite is a chromium-bearing garnet group. Chromium tends to make minerals green. It forms in super-fine green crystals, so it’s usually mounted on jewelry in the rough (druzy) so it can sparkle.

Andradite

Andradite

AKA: Melanite (Black), Topazolite (Yellowy), Demantoid (Green).

It’s one of the rarest, most expensive kinds of garnet -scratch that- gem there is period. For Demantoid, we’re talking $1000-$2000 per carat… if you’re buying lots of tiny ones in bulk. A really nice 2.5ct specimen would cost about as much as a new car. Andradite is a calcium-iron garnet. Andradite is found both in deep-seated igneous rocks. Demantoid has been called the “emerald of the Urals” from its occurrence there.

Grossular

Grossular

AKA: Hessonite (Cinnamon), Tsavorite (GREEN).

Grossular is a calcium-aluminium garnet. The name grossular is derived from the botanical name for the gooseberry, grossularia, in reference to the green garnet of this composition that is found in Siberia. It rare to find large gem quality bits of Tsavorite that aren’t included (flawed), so it’s pricey, but not as much as Demantoid.

Garnet 3

I regret to inform you that garnet doesn’t come in Geode form. I know we’re all deeply saddened by this, but all is not lost. Almandine garnets can display Asterism. Asterism is kind of like a form of Chatoyancy (think Tiger’s Eye or Cat’s Eye) that manifests in the shape of a star. The star will move with you no mater what angle you view it from. Remember when I said Almandine was nothing to write home about? I WAS LYING. ALL GARNETS ARE MAGNIFICENT.

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Fact List, Minerals,

Last Update: April 25, 2016

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