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Garnet is January’s birthstone and the anniversary
gemstone for the second year of marriage. Garnet derived its name from the
Latin word granatus, meaning like a grain, which refers to the mode of
occurrence wherein crystals resemble grains or seeds.
The most frequently occurring color for garnet is red.
However you can find garnets in also every color, with the exception of
blue. Garnet are found in different shades of green, pale to bright yellow,
fiery orange and fine earth- and umbra-shades. There are a number of
garnets; Hessonite is a fine orange, cinnamon brown, or pinkish variety of
grossularite, while tsavorite is the trade name for fine dark green
grossularite. Melanite is a black titanium bearing variety of andradite and
demantoid is a rich green variety. Malaya is a trade name for a
pyrope-spessartite that varies in color from red, through shades of orange
and brownish orange to peach and pink. Rhodolite is a purplish red
pyrope-almandite.
Almandine: Orangy red to purplish red
Almandine-spessartine: Reddish orange
Andradite: Yellowish green to orangy yellow to black
Demantoid: Green to yellow green andradite
Topazolite: Yellow to orangy yellow
Grossular: Colorless; also orange, pink, yellow, and brown
Tsavorite: Green to yellowish green
Hessonite: Yellow orange to red
Pyrope: Colorless; also pink to red
Chrome pyrope: Orange red
Pyrope-Almadine: Reddish orange to red purple
Pyrope-Spessartine: Greenish yellow to purple
Malaia: Yellowish to reddish orange to brown
Color-change garnet: Blue green in daylight to purple red in
incandescent light
Rhodolite: Purplish red to red purple
Spessartine: Yellowish orange
Uvarovite: Emerald green
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Garnets "Mozambique" |
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Color: |
Red, brown, orange, yellow, green, blue, violet, colorless and black. |
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Cleavage: |
Imperfect |
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Fracture: |
Subconchoidal, usually brittle. |
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Heat sensitivity: |
Low to none, imperfections like tiny cracks and bubbles can be intensified
by heat. Rhodolite tends to be the most heat sensitive garnets |
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Pleochroism: |
None |
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Birefringence: |
double refraction, only in rhodolite. |
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Crystal structure: |
Isometric, rhombic, dodecahedron. |
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Mozambique: |
iron aluminum silicate - iron is the red colorant |
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Color: |
Deep red with a wine to brown undertone. |
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Moh’s hardness: |
7.5 |
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Refractive index: |
1.78-1.83 |
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Specific gravity: |
3.95-4.25 |
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Dispersion: |
Moderately high (.024-.027) |
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