Demantoid Garnet

Demantoid garnet is by far the most rare and valuable garnet. Fine pieces can command prices similar to fine ruby or sapphire. These garnets are special because they have similar properties to diamonds (hence the name). For example, they have very high dispersion or “fire” (ability to reflect light in rainbow colors) and very high luster, which basically means they are really really sparkly. It is extremely rare to find demantoid garnets over a carat or so in size. Perfect clarity is also quite rare. In fact, some demantoid garnets have characteristic inclusions called “horsetails” – if you see these in the stone (under magnification), you know it is demantoid garnet.

Horsetail inclusions in demantoid garnet

Close up of horsetail inclusions in demantoid garnet

The Most Valuable Demantoid Garnet

The most valuable demantoid garnet is large (over 1 carat), perfectly cut with brilliant “fire”(dispersion), with very good clarity except for fine “horse tail” inclusions, and intense bright green color.

Lowest Value: These garnet beads have terrible clarity. They are so included that they were made into beads instead of being faceted. We cannot see any rainbow :”fire”. The color of these beads is also brownish and dull. These peices are examples of the least valuable demantoid garnet. Medium Value: This demantoid garnet has a very poor cut. The facets are random and uneven and it does not reflect and split light as well as it should. The color is also somewhat murky – not bright. Otherwise, it is of a good size and pretty good clarity. High Value: This demantoid garnet is of a good size (over 1 carat) and good cut. It shows strong dispersion (rainbow reflections). It also has an intense (though too dark) color. The main fault of this gemstone is its very poor clarity. Highest Value: While the color of this garnet could be stronger, it does have excellent clarity andcut and is over 1 carat. This is about as good as it can get.



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