A family of gemstones, most often dark red (darker than a ruby). It can come in many different shades, mostly in the red-orange-brown family, but sometimes blue, green, yellow, and so dark as to seem black.

    Types of garnets:
  • Almandine is a deep red which gets its color from iron. This is what most people think of when they think of garnets. Occasionally inclusions in these stones form an asterism, or a star garnet.
  • Pyrope is a cherry-red, colored by chromium, with no brown undertones as almandine has.
  • Rhodolite is a stone which is part almandine, part pyrope; it is most commonly described as raspberry-colored, but can even be pink or purple.
  • Spessartine is an orange-red or plain orange stone, also called "Mandarin garnet." These are becoming more popular on the market in the 1990s; before then they were rarely seen.
  • Malaia garnet is a mixture of almandine, pyrope, and spessartine; rutile inclusions are fairly common in these stones.
  • Grossularite is a yellow gem with a hint of green in its color; these can be easily mistaken for peridot.
  • Hessonite is a golden brown stone, which looks like a hyacinth zircon.
  • Tsavorite is a light emerald green garnet primarily found in Kenya. Its color is caused by vanadium in the stone. It's one of the most expensive garnets because it has a limited supply and a popular color.
  • Demantoid (also called andradite) is a rare green garnet (light green like a peridot) which was discovered in Russia in the mid-1800s. It often contains curved asbestos fibers inside the stone. It was fairly popular in Victorian times, and jewelry from that era with these stones is expensive because the supply is limited.
  • Uvarovite garnet is bright green and quite brittle; this makes it difficult to cut for jewelry. Its supply is also sporadic and it's not much seen on the market.

Minerology

Unlike some other gems, garnets can possess any of a number of chemical configurations. The name "garnet" is actually a blanket term for all these crystals, which share similar physical properties.

The general chemical formula for a garnet is A3B2(SiO4)3, where A can be calcium, magnesium, iron, or manganese, and B can be aluminum, iron, chromium, or in rare instances, titanium. The most common forms are pyrope (magnesium and aluminum), almandine (iron-aluminum), and rhodolite (a pyrope-almandine combination). Other common variations include spessartine (manganese-aluminum), grossular (calcium-aluminum), andradite (calcium-iron), and uvarovite (calcium-chromium). It usually forms a dodecahedral crystal and has a mineral hardness of 6.5 to 7.5.

Garnets are most commonly a dark red hue, but because it has so many chemical variations is can be found in any color except blue. A few garnets even change color when viewed under natural or incandescent light. Because of this, garnets are sometimes mislabeled (either creatively or misleadingly) as, for example, "American ruby" or "Oregon jade".

History

The word "garnet" is derived from the Latin word granatus, "grain", referring to the way crystals resemble grains or seeds embedded in the crystalline matrix. It has been used as a gemstone since prehistory, but was first used industrially to coat sandpaper in 1878. Today, industrial use of garnets outpace its use as a gemstone by about five hundred times.

Ancient Egyptians were known to use garnet gemstones as early as 3500 BC. Asiatic tribes carved garnets into bullets in the belief that their fiery color would inflict more deadly wounds. In ancient Greece, Alexander the Great popularized the cutting of cameos from gemstones and garnets (mainly pyrope, from Greek pyropos meaning "fire-eyed") were widely used for this purpose. Persians considered garnet to be a royal stone suitable for bearing the image of their king.

Today

Garnet is still known as the gem of faith, constancy, fidelity and truth. It is inexpensive and often used in children's jewelry. It is mined both for industry and jewelry throughout the world, included the United States, Africa, India, Sri Lanka, and Brazil.

Garnet is the birthstone for the month of January and is the symbolic gemstone for the second wedding anniversary.

Gar"net (?), n. [OE. gernet, grenat, OF. grenet,grenat, F. grenat, LL. granatus, fr. L. granatum pomegranate, granatus having many grains or seeds, fr. granum grain, seed. So called from its resemblance in color and shape to the grains or seeds of the pomegranate. See Grain, and cf. Grenade, Pomegranate.] Min.

A mineral having many varieties differing in color and in their constituents, but with the same crystallization (isometric), and conforming to the same general chemical formula. The commonest color is red, the luster is vitreous, and the hardness greater than that of quartz. The dodecahedron and trapezohedron are the common forms.

⇒ There are also white, green, yellow, brown, and black varieties. The garnet is a silicate, the bases being aluminia lime (grossularite, essonite, or cinnamon stone), or aluminia magnesia (pyrope), or aluminia iron (almandine), or aluminia manganese (spessartite), or iron lime (common garnet, melanite, allochroite), or chromium lime (ouvarovite, color emerald green). The transparent red varieties are used as gems. The garnet was, in part, the carbuncle of the ancients. Garnet is a very common mineral in gneiss and mica slate.

Garnet berry Bot., the red currant; -- so called from its transparent red color. -- Garnet brown Chem., an artificial dyestuff, produced as an explosive brown crystalline substance with a green or golden luster. It consists of the potassium salt of a complex cyanogen derivative of picric acid.

 

© Webster 1913.


Gar"net, n. [Etymol. unknown.] Naut.

A tackle for hoisting cargo in our out.

Clew garnet. See under Clew.

 

© Webster 1913.

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