Usually orange to reddish brown, gem-quality spessartite or spessartine garnets are somewhat rare. However, as blends with other garnet species, they include popular mandarin and malaya garnets as well as color change gems. Spessartites make very durable jewelry stones.
Spessartite Garnet Value
Before the discovery of mandarin garnets in the 1990s, bright, orangish reds were the most valuable spessartite colors. These came most famously from Ramona, California and Amelia County, Virginia in the United States. These spessartites remain very rare and valuable.
Spessartite usually occurs in a solid-state series or blend with other garnet species, such as almandine and pyrope. Gems closer to a pure spessartite content have a light orange color. Those with a reddish to red-brown hue have a higher almandine content as well as a higher refractive index.
Mandarin garnets have the highest percentage composition of spessartite (85-95% mol) and have vivid orange colors. Malaya garnets can have compositions of variable but high percentages of spessartite (2-94% mol), pyrope (0-83% mol), and almandine (2-78% mol). Their colors range from pink, pinkish orange, yellowish orange, orange, to red.
Large spessartite stones are very rare and usually quite dark.
Spessartite or Spessartine?
Both “spessartite” and “spessartine” are used in gemology to describe the same species of garnet. Originally, “spessartite” was the favored usage in the United Kingdom, while “spessartine” was more popular in the United States. Either term is acceptable when referring to these garnets.
Be aware, however, that the term “spessartite” is used to refer to a type of lamprophyre igneous rock also named after the Spessart Mountains of Germany. Context and appearance should suffice to distinguish them.
A rare and spectacular variety of spessartite discovered in Azad Kashmir, Pakistan has been marketed as “Kashmirine.” Its color ranges from slightly yellowish orange to brownish orange or red-orange.
Spessartite is part of the composition of many color change garnets. Most such gems are pyrope-spessartite blends.
Unusual color change garnets with large amounts of vanadium (V) and chromium (Cr) have been reported from East African sources. These are primarily spessartite with unusually large components of grossular. Some of the color changes observed include the following:
Greenish yellow-brown (transmitted fluorescent light) to purplish red (reflected fluorescent); reddish orange to red (incandescent light). Spessartite/grossular/almandine, N = 1.773, SG = 3.98.
Light bluish green (transmitted fluorescent) to purple (reflected); light red to purplish red (incandescent). Spessartite/grossular/pyrope, N = 1.763, SG = 3.89.
Garnets with alexandrite-like color change have also been noted, from violet-red to blue-green. These are usually small, but a 24.87-ct stone was sold in 1979.
An online search will easily find “synthetic spessartite/spessartine” jewelry for sale. However, some of these sites will also explicitly equate colored cubic zirconia (CZ) or synthetic corundum with “synthetic spessartite.” These are distinct species, not garnets, and would be better described as imitations or lookalikes. (Most likely, these vendors treat the term “synthetic” as synonymous with “imitation”).
Even rough material may be misrepresented. In at least one instance, lab-created corundum was sold as natural spessartite rough.
An early 20th century gold brooch designed as an insect. It has a body made from an old-cut diamond and oval spessartite, tsavorites for eyes, single-cut diamonds for wings, and a split pearl terminal bar. 5.2 cm in length. Photo courtesy of liveauctioneers.com and Fellows.