When people think of garnets, they typically think of a bright red gemstone. However,
not all garnets are red. Garnets can be a number of colors which include orange, yellow, black,
and even green! This video will discuss eleven unique varieties of garnet, and how they formed.
The varieties of garnet in this video are sorted by their coloration. The first variety we will
cover is the pyrope garnet. This variety of garnet is the most purchased variety of garnet.
It has a dark red coloration. This garnet variety contains magnesium and aluminum in its
crystal structure. In Arizona, a number of these garnets are naturally mined by a species of ant,
which are then placed on an anthill and are thus referred to as "ant hill" garnets.
The second variety of garnet is referred to as an almandine garnet. This variety of garnet has
a dark red coloration which is only slightly lighter in coloration than a pyrope garnet.
This garnet has the same chemical formula as pyrope garnets, except the magnesium atoms are
replaced with iron. Almandine garnets are the most widely used industrial variety of garnet.
Small amounts of it are mined for use in abrasive blasting, waterjet cutting, and water filtration.
The variety of garnet shown on screen is known as a Malaia garnet. It is a subvariety of pyrope
garnet which instead of being dark red has a pinkish orange or reddish orange coloration.
This variety is quite valuable, and often sells for more than five hundred dollars a carat.
One of the best sources of this garnet variety is Tanzania.
A spessartine garnet is a garnet variety widely prized for its orangish red or
deep orange coloration. This type of garnet is one of the hardest varieties, and thus
is less likely to break in jewelry (mohs hardness 7 to 7.5). A spessartine garnet
contains manganese in its crystal structure, which helps create the unusual coloration.
This unique orange garnet is known as a Hessonite garnet. The name of this gemstone comes from the
Greek word hesson, which means inferior. This variety is referred to as inferior,
as it is one of the softest varieties of garnet and has little commercial use.
Hessonite garnets typically sell for around fifty dollars a carat when used in jewelry.
A topazolite garnet gets its name from its unique yellow coloration, which can resemble
a yellow topaz. Although topazolite garnets can be found around the world, some of the
best specimens are mined in northern Italy. It attains a premium price in jewelry, especially
in pieces which contain a spectacular amount of fire in them such as this piece shown on screen.
In my field studies, this is the most common variety of garnet which I have collected in
Arizona and New Mexico. Known as a grossular garnet, this variety can be a number of colors
but is most commonly a pale green color. Despite how seemingly common this variety is, it attains
the highest price per carat on the jewelry market at around seven hundred dollars a carat.
An andradite garnet can be a number of colors, but is most prized when it is solid green
or greenish yellow. This variety of garnet contains both calcium and iron
in its crystal structure. It has been found on every continent, and even on a few meteorites.
The ninth variety of garnet is my personal favorite. Known as uvarovite, this is a very
rare chromium rich garnet. It has a deep emerald green color to it, and is rarely found in crystals
large enough to facet. Here are a few museum grade specimens of this gorgeous variety of garnet.
This variety of garnet is prized for its unique purpleish pink coloration. Known as a rhodolite
garnet, it is actually an unusually colored variant of a pyrope garnet. Surprisingly, this
gemstone is quite affordable. It can be purchased for less than two hundred fifty dollars per carat.
The last garnet variety I will cover is a variety of andradite garnet which contains
a black coloration. This variety is known as a melanite garnet. Melanite garnets have
a black coloration due to a high amount of titanium dioxide in its crystal structure,
which is usually around 5% by weight. There are numerous other subvarieties of
garnets, so I just picked the eleven varieties which stood out the most.
I hope that you enjoyed this video! If you would like to request a specific topic,
please leave a comment below!