Garnets have a long and ancient history, from the beaded necklaces of Egyptian pharaohs, to the carved signet rings of Ancient Rome, to the pavé jewelry of the Victorian Era. These days, January’s birthstone is no longer only for the privileged, and it makes the perfect addition to your jewelry collection. Here are ten important varieties of garnets you should know.
Red garnets are the most prevalent and well-known, but this gem is also found in green to greenish yellows, orange to orange pinks, purple, blue, and even color changing varieties. The term garnet refers to a group of closely related minerals that includes over twenty species, and then even more varieties within those species. The five main species of gem-quality garnets are pyrope, almandine, grossular, andradite, and spessartine. Garnets are found all over the world in many varieties.
Here are some of the more popular types of garnets you’ll see in jewelry:
Pyrope garnet is the most popular of the red varieties, with that rich pomegranate color that most people associate with garnets. The word pyrope derives from the Greek word for “fire-eyed”, in reference to the high refractive index of this species of garnet. Pyrope garnets gained popularity after large deposits were discovered in Bohemia (which later became Czechoslovakia) in the 16th century. A fashion for Bohemian garnet jewelry would later emerge, with rose cut garnets set into tight pavé clusters, and reached its peak towards the end of the Victorian Era.
Almandine is another species of red garnet. Most almandine garnets are opaque, so gem-quality transparent specimens are considered rare. This type of garnet can range from purplish red to dark red. Almandine is also found in the form of star garnets. Red garnets are found all over the world, with deposits on every continent.
First discovered in the Ural Mountains of Russia in the 1860’s, demantoid garnets are a rich forest green variety of the andradite garnet species. Demantoid garnets, though rare, are popular in jewelry because of their high refractive index. Its name derives from the German word for diamond, referring to its adamantine luster. In addition to their excellent fire, demantoid garnets are known for their horsetail-like inclusions that display as a wispy spray. This characteristic, prized by collectors, is found in specimens from Russia, Iran, and Italy. Demantoid garnets are also mined in Namibia and Madagascar. After their initial discovery, demantoid garnets became highly coveted within the European aristocracy, so you will often see them in fine Victorian jewelry.
Tsavorite garnets are sometimes confused with demantoid garnets because of their color. Tsavorite garnets are of the grossularite species, and do not have the horsetail inclusions found in demantoid garnets. Tsavorite garnets also lack the fire of their green counterpart, however what they lack in light dispersion, they make up for in rich, vibrant color. This variety of garnet is relatively recent in jewelry, as it wasn’t discovered until 1967, when it was found in Tanzania. It eventually got its name when deposits were found near Tsavo National Park in Kenya.
Mali garnets have a beautifully unique color, which can range from a golden to chartreuse yellow, brownish green, or rarely, a mint or chrome green. Mali garnets are also unique because they are a hybrid of two different garnet species: grossular and andradite. The dominating composition of grossular gives this variety its color, while the small andradite component gives Mali garnets their fire. As their name implies, this variety was discovered in the West African country of Mali in 1994.
Hessonite garnet is a unique variety of grossular garnet, in that it is an orange-brown color, rather than the typical green. Although sometimes confused with citrine or topaz, hessonite garnets can be distinguished by their characteristic inclusions, which appear as curving areas of varying translucency. Primarily mined in Sri Lanka, it is also found in Brazil, India, Canada, Madagascar, and Tanzania. Hessonite garnet is one of the nine planetary gemstones in Vedic astrology, and is believed to promote success, wealth, and longevity.
Spessartite (or spessartine) garnet is orange to orange-red in color. Spessartite garnets have a high refractive index that gives them a luscious fire and brilliance when cut. The name derives from the forested mountain region in Germany where it was discovered in the 1880’s. Despite this early discovery, spessartite wasn’t commonly used in jewelry until more recent discoveries in Namibia and Mozambique. This variety is also found in Myanmar, Brazil, China, Sri Lanka, Kenya, Madagascar, Tanzania and the U.S.
Named after the Greek word for rose, “rhodon”, rhodolite garnets range in color from pink to purplish red. This variety is another species hybrid, classified as both pyrope and almandine. Rhodolite garnets are usually free of inclusions and flaws which, combined with their beautiful color, make them highly desirable for use in jewelry. Rhodolite garnets can be a more affordable alternative to purple and pink sapphires. This garnet variety is mined in Tanzania, Mozambique, Brazil, Sri Lanka, and North Carolina in the U.S.
Ant hill garnets are wonderfully unique, in that they are “mined” by ants. As they dig and build their home, the ants bring up small garnets along with the grit and dirt. These gems fall to the base of the hill, where they are found by collectors. Due to the nature of how they are mined, ant hill garnets are usually less than one carat. This phenomenon is best known to occur in the Navajo reservation of Arizona. The pyrope garnets found there are a deep, dark red color.
Color change garnets are rare and highly desirable for collectors. In different specimens, the color change can be from greenish yellow to purplish red, or from blueish green to blueish purple. This color characteristic is due to the combination of various mineral compositions of three or more garnet species. Unlike natural alexandrite (another color changing gem), color change garnets are commonly available in sizes over one carat. Important sources for this variety of garnet include Tanzania, Sri Lanka, Madagascar, Norway, and Idaho in the U.S.
Star garnets are so named because they display an asterism. You’ll see this as a star-like reflection of light that moves around the stone depending on how you hold it. This asterism can occur in almandine and pyrope-almandine species. Star garnets are cut into cabochons to best show off their properties. Most specimens will have stars with four rays, and very rarely, six rays. Commercially sourced star garnets are only found in Idaho in the U.S. and India.
With all the colors and varieties available, there’s definitely a garnet for everyone. Click here to shop Market Square Jeweler’s garnet collection.