Spessartite

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Spessartite Garnet
Chemical composition Mn3Al2(SiO4)3

Manganese aluminum silicate

Crystal system Cubic
Habit Dodecahedra
Cleavage None
Hardness 7
Optic nature Isotropic
Refractive index 1.795-1.815
Birefringence None
Specific gravity 4.12-4.20
Lustre Vitreous
Nigerian Spessartite garnet
Photo courtesy of Lembeck Gems

Spessartite image gallery

Spessartite is also named spessartine, both names are used interchangeably.

Diagnostics

Color

Red, reddish-orange to yellowish-brown.

Spectroscope

Spessartite shows a typical spectrum due to manganese (idiochromatic) and some iron (from almandine).

Inclusions

  • Feathers of liquid droplets ("shredded inclusions"), negative crystals.

Specific gravity

Spessartite sinks in all common heavy liquids.

Chelsea Colour Filter

Spessartite will show red under the CCF.

Varieties

Mandarine/Kashmirine/Hollandine

Three names for the same intense orange variety of spessartite.

Malaia

Main entry: pyrope

Malaia garnet (or malaya garnet) is the red-orange variety of pyrope-spessartite.

Inclusion images

Inclusions in a manderine garnet
Photo courtesy of John Huff, gemcollections.com


Localities

  • Sri Lanka (Ceylon)
  • Burma
  • Brazil
  • Madagascar
  • Mozambique
Faceted Mozambique Spessartite garnet
Photo courtesy of The Gem Trader

  • Nigeria
  • Namibia
  • California