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Spessartite Faceting Information


A guide to Spessartite Faceting Information. Essential information on Glass faceting that includes tips on cuts and polishes together with helpful details.

By Jeff R. Graham, updated on

Spessartite (Garnet)

Spessartite Garnets

Color: Orange to red brown
Moh's Hardness: 7-7.5
Refractive Index: 1.79-1.81
Critical Angle: 33.96°
Specific Gravity: 4.12-4.20
Cleavage: Imperfect
Fracture: Subconchoidal
Heat Sensitivity: Slightly
Birefringence (double refraction): 0.027
Crystal Structure: Isometric, rhombic, dodecahedron,icositetrahedron

Treatments: Generally none

What I prefer to polishing with: Alumina oxide with a tin lap (scored).

Jeff's Comments: Most Garnets cut and polish pretty easily (with the exception of a piece with bubbles/flaws) and are really not much of a problem. Pre-polish with a 1200 steel (not Nu Bond, it will leave orange peel) and polish with tin lap.

Design Notes: Most of the orange/brown/red types of Garnet are saturated and I prefer checker boards and bar cut in them. On lighter Grossular Garnets and Mail types of Garnets I prefer a deeper design.

Design Links:
Tic Tac - Good for dark material
Smith Bar - Great for any material
Brilliant Pear - Nice in about anything

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