Garnet Facts - Geology of the World

These geometric gemstones are often red in color and interestingly shaped, making them commonly used in jewelry and furniture.

5. Description

Garnet is a gemstone found within a variety of minerals that typically shines with a bright red color. Recent research has shown there are many different spectrums of light passing through the gem, though red remains the most dominant. It leaves a colourless streak, and has a hardness of between 6.5 and 8.0 Mohs. It may be sourced from igneous, sedimentary, or metamorphic rocks, and its appearance ranges from transparent to opaque in color, depending on the area in which the rock was found, and its state of purity and polish. Today, there are approximately four dominate types of Garnet. Namely, these include Pyrope, Almandite, Spessartite, and Grossularite.

4. Location

It is suggested that the first uses of Garnet were in Ancient Egypt. It was subsequently worn as personal ornamentation by Pharaohs and religious figures, as well as being used to enhance the look of furnishings and statues. Today, different types of garnet are found across different parts of the globe. Pyrope Garnet is located in Brazil, India, Sri Lanka and Thailand. Almandite is found in parts of Brazil, India, Madagascar, and the US. Spessartite is also found in Brazil, as well as China, Kenya, and Madagascar. Last but not least, Grossularite garnet is found in Myanmyar, South Africa and Zambia.

3. Formation

Garnet is generally found inside of metamorphic rock. It may also be found within some igneous rocks, though this is not as common. This means they are formed under high temperatures and high pressure which cause these isometric crystals to form. After formation, garnet crystals are commonly red in color. Garnet gemstones normally form in either a cubic pattern or a twelve-sided rhombic pattern. Under uneven pressure, they may form unevenly and irregularly.

2. Uses

Without a doubt, Garnet is a beautiful natural marvel to look at, a feature which has made it great for uses in making jewelry and furnishing decorations. Along with this, Garnet is also used in many industrial materials, especially as an abrasive for finishing and polishing other hard materials. Due to its own hardness, it works well in cutting materials and sanding, and is also used as a filtration medium for liquids. At times, Garnet gems are brought up to the Earth’s mantle through eruptions which cause pipe tunnels called “xenoniths” to appear, which are often home to Garnet and Diamond deposits. Due to the unique color of Garnet, it is usually compared to different parts of the surrounding rock in order to distinguish it from diamonds.

1. Production

Four countries worldwide remain dominate in Garnet production today. These are India, China, Australia, and the United States. India leads the globe in production, with 700,000 metric tons of Garnet. China follows in second place with 470,000 metric tons. Australia lands in third, with 150,000 metric tons, with the United States providing around 54,000 metric tons itself to garner a fourth place position in nationwide garnet production. The mineral is mined in these and other countries, and prices may vary greatly depending on the type of Garnet and its aesthetic characteristics. Typically, Spessartite is the most expensive, selling at $40-$50 USD per carat, although some extravagant Garnets can sell for as much as $100 USD per carat. The cheapest versions of Garnet are Almandine, Pyrope, and Rhodolite, which each typically sell for around $20-$30 USD per carat.

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