Demantoid Garnet Faceting
Essential information on demantoid faceting / facet garnet. Read up on the cuts, polishes, tips and a detailed guide on demantoids and learn more about it.0
- "Demantoid Garnet," fancy Barion barrel cut, 0.71 cts, Madagascar. © Dan Stair Custom Gemstones. Used with permission.
Color: Green, Emerald Green
Moh's Hardness: 6.5-7
Refractive Index: 1.88-1.89
Critical Angle: 32.13°
Specific Gravity: 3.82-3.85
Heat Sensitivity: Yes
Birefringence (double refraction): 0.057
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: Typically has horse hair type inclusions/needles, seldom over a gram rough (usually 1-3 carats). Rough is hard to find...
Design Notes: Design choice is limited by the small size and inclusions, I generally cut a simple checker board that is as deep as I can cut from the rough.
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