Garnet

Other Silicates & Gemstones

Garnet is a group of closely related silicate minerals that share a cubic crystal structure but differ in composition. Although deep red is familiar, natural garnets also occur in orange, yellow, green, purple, pink, brown, and rare blue varieties.

Identity

Material or variety: Garnet group
Scientific or material identity: Garnet group
Classification: Natural mineral or mineral variety
Composition or formula: X₃Y₂(SiO₄)₃
Crystal system or structure: Cubic
Geological or manufacturing origin: Can form in more than one geological environment, or combines several materials.
Mohs hardness: 6.5 to 7.5

Origins

Czech Republic · India · Madagascar · Sri Lanka · Tanzania

Appearance & optical properties

deep wine-red translucent garnet.

History & discovery

The name comes through Middle English and Old French from Latin granatus, probably comparing red crystals with pomegranate seeds. Garnets have served as gems since the Bronze Age; Roman signet rings used carved stones, and Bohemian deposits supported a major European jewelry industry from about 1500.

Uses & care

Common uses: Transparent garnets are faceted or carved for jewelry. Tough garnet grains are also used in coated abrasives, abrasive blasting, high-pressure waterjet cutting, polishing, and water-filtration media.
Handling and cleaning: Clean garnet with warm soapy water. Protect it from hard blows and rough wear; steam cleaning is not recommended, and ultrasonic cleaning should be avoided for fractured or fracture-filled stones.

Jewellery

7 pieces of Garnet jewellery. Learners earn each one in DigMyGem by learning words; until then it shows as a silhouette.

Lion of Merelani
Jewel
A 116.76-carat square-cushion tsavorite, a vivid green garnet, cut by Victor Tuzlukov from a crystal found near Merelani in Tanzania. It is the largest precision-cut tsavorite in the world and is held at the Smithsonian.
Photo: Robert M. Lavinsky, CC BY-SA 3.0, via Wikimedia Commons
Sutton Hoo purse-lid
Jewel
A gold and garnet purse-lid from the early seventh-century Anglo-Saxon ship burial at Sutton Hoo, its cloisonne panels of red garnet set over gold foil that makes the stones glow. It is kept by the British Museum.
Photo: Geni, CC BY-SA 4.0, via Wikimedia Commons
Bohemian Garnet Necklace
Necklace
A necklace of small rose-cut Bohemian garnets set so closely that the stones read as one river of fire. It was made for evening wear, when candlelight made the deep red flare.
Winfarthing pendant
Pendant
A seventh-century Anglo-Saxon gold disc pendant, found in an undisturbed grave near Diss, Norfolk in 2014, inlaid with hundreds of tiny garnets. It is displayed at the Norfolk Castle Museum.
Photo: Portable Antiquities Scheme from London, England, CC BY 2.0, via Wikimedia Commons
Forsbrook Pendant
Pendant
A seventh-century Anglo-Saxon setting of a fourth-century Roman gold coin, in gold cellwork with garnet and blue glass inlays, found at Forsbrook, Staffordshire and bought by the British Museum in 1879.
Kingston Brooch
Brooch
The largest known Anglo-Saxon composite disc brooch, a seventh-century piece of gold inlaid with blue glass, white shell, pearl and garnet, now in the World Museum Liverpool.
Photo: Reptonix free Creative Commons licensed photos, CC BY 3.0, via Wikimedia Commons
Sutton Hoo helmet
Jewel
An Anglo-Saxon helmet of about 620 AD from the Sutton Hoo ship burial, decorated with gold and garnet cloisonne panels. It is one of the best-known objects in the British Museum.
Photo: user:Geni, Public domain, via Wikimedia Commons