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Almandine
Salida, Colorado

This specimen measures 5cm in diameter

Garnet group
     Mg₃Al₂Si₃O₁₂(pyrope)
     Fe₃Al₂Si₃O₁₂(almandine)
     Mn₃Al₂Si₃O₁₂(spessartine)
     Ca₃Al₂Si₃O₁₂(grossular)
     Ca₃Fe₂Si₃O₁₂(andradite)
     Ca₃Cr₂Si₃O₁₂(uvarovite)

Nesosilicates; aluminum and calcium silicates

Color and Luster: Vitreous; colorless streak
Pyrope is a deep red to reddish black,
(Var. Rhodolite) is a puple or rose to pale purplish red
Almandine is a deep red to brown, brownish black
Spessartine is a brownish red to hyacinth-red
Grossular is colorless, white, yellow, pink, green, or brown
Uvarovite is emerald green
Andradite is wine-red, greenish(Var. demantiod), yellow (Var. topazolite), brown, or black(Var. melanite)

Hardness: 6.5-7.5

Cleavage: None; parting sometimes distinct in six directions

Fracture: Conchoidal, uneven, brittle

Crystals: Isometeric; crystals very common as dodecahedrons and trapezohedrons; also granular, lamellar, compact, disseminated

Photo by Mary Sutherland

Descriptions taken from
The Audubon Society Field Guide to North American Rocks and Minerals