Grossular Faceting Information

Faceting Information such as details, guides, tips and tricks. Choose which best fit the criteria for Grossular gemstones together with helpful details.


Grossular Garnet

Color: Green yellow, copper, brown
Mohs Hardness: 7.5
Refractive Index: 1.73-1.75
Critical Angle: 35.31°
Specific Gravity: 3.60-3.68
Cleavage: Imperfect
Fracture: Subconchoidal
Heat Sensitivity: Moderate
Birefringence (double refraction): 0.027
Crystal Structure: Isometric, rhombic, dodecahedron, icositetrahedron

Tsavorite Garnet - Green - vanadium is the green colorant. It is usually only available in small sizes and care must be taken when cutting because it tends to cut dark stones. I usually cut checker boards and opposed bars in larger rough.

Treatments: Generally none

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

Jeff's Comments: This is some of my personal favorite material to cut, Mail Garnets in particular. Most Garnets cut and polish pretty easily (with the exception of a piece with bubbles/flaws) and a re 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: I prefer these in deep brilliant designs, the sparkle is diamond like.

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

Jeff R. Graham

The late Jeff Graham was a prolific faceter, creator of many original faceting designs, and the author of several highly-regarded instructional faceting books such as Gram Faceting Designs.

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