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Garnet

Garnets are a set of closely related minerals forming a group, with gemstones in almost every color.

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Intense

The best colors for spessartine are vivid orange to orangy red.

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Clean

No eye visible inclusions present is rare for spessartine.

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Bright

The intense color, lack of inclusions and skillful cutting create a bright stone.

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Cinnamon

This specimen is hessonite garnet also called the cinnamon stone for its color.

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Array of faces

An amazing intergrowth of hessonite garnet crystals creates an array of crystal faces.

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Mineral Specimen

Hessonite garnet specimens are attractive and collectible.

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Tools

Overview

About Garnet

Red garnets have a long history, but modern gem buyers can pick from a rich palette of garnet colors: greens, oranges, pinkish oranges, deeply saturated purplish reds, and even some blues. Red garnet is one of the most common and widespread of gems. But not all garnets are as abundant as the red ones. A green garnet, tsavorite, is rarer and needs rarer rock chemistries and conditions to form.

Garnet Description Garnet History and Lore

Birthstones & Anniversaries

Garnet is the birthstone for January and the gem for the second anniversary.

Tsavo Park

Campbell Bridges mined tsavorite garnet in Kenya near Tsavo National Park.


Faberge

The imperial Russian jeweler created intricate jewelry designs for demantoid garnet.


3800 BC

A stylish red garnet bead necklace found in a grave in Egypt is more than 5,000 years old.


Facts

  • Mineral: Garnet group
  • Chemistry:
  • Almandine- Fe3Al2(SiO4)3
  • Andradite- Ca3Fe2(SiO4)3
  • Grossular- Ca3Al2(SiO4)3
  • Pyrope- Mg3Al2(SiO4)3
  • Rhodolite- (Mg, Fe)3Al2(SiO4)3
  • Spessartine- Mn3Al2(SiO4)3
  • Color: All colors
  • Refractive index: 1.714-1.888
  • Birefringence: None
  • Specific gravity: 3.47-4.15
  • Mohs harness: 6.5-7.5

Where It's Found

map

Treatments

There are a number of processes used to alter the color, apparent clarity, or improve the durability of gems.

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Synthetics

Some gemstones have synthetic counterparts that have essentially the same chemical, physical, and optical properties, but are grown by man in a laboratory.

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Imitations

Any gem can be imitated—sometimes by manmade materials or by natural materials chosen by man to impersonate a particular gem.

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gem love

Why We Love This Gemstone

1
Gemological Challenge

Figuring out how each new gem garnet fits into the six main mineral species is a challenge for gemologists.

2
Horsetail Inclusions

Horsetail inclusions in green demantoid garnet are one of the few internal features that increase a gem's value.

3
Fire

Due to demantoid garnet's high dispersion, well-cut, fashioned gems display an amazing amount of fire.

Quality Factors

When deciding which garnet to buy, think of garnets in terms of color.

Color

quality factors

Garnet includes affordable dark red varieties, rare and valuable greens, and many colors in between.

Clarity

quality factors

Garnet clarity often depends on garnet type. Red garnets often don’t have eye-visible inclusions.

Cut

quality factors

Many garnets are cut into standard shapes and calibrated sizes to allow setting into manufactured jewelry.

Carat Weight

quality factors

Garnets can be found in all sizes and weights, although some varieties are rare in large sizes.

Garnet Quality Factors: The Comprehensive Guide

Research

Explore sources, gemological research, and the role of gems in history.

A Proposed New Classification for Gem-Quality Garnets

Carol M. Stockton and D. Vincent Manson , Dec 1, 1985 Read Article

Summer 2012 Gem News International

, Jun 1, 2012 Read Article

Fall 2011 Gem News International

, Sep 1, 2011 Read Article

Summer 2007 Gem News International

, Jun 1, 2007 Read Article