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Zincite Faceting Information


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

By Jeff R. Graham, updated on

Zincite (zinc oxide)

Zincite parcel

Color: Orange, red and yellow, leek-green, light blue to colorless. Moh's Hardness: 4-4.5
Refractive Index: 2.02
Critical Angle: 29.67°
Specific Gravity: 5.6
Cleavage: Perfect
Fracture: Subconchoidal, brittle
Dispersion: .127
Heat Sensitivity: Low
Birefringence (double refraction): Medium (.016)
Crystal Structure: Hexagonal

Treatments: None

What I prefer to polishing with: Tin lap with Alumina oxide. Zinc laps with 8,000 pre-polish and 50,000 polish. Specta Ultalaps work pretty well. It tends to scratch and chip during polishing and can be problematic.

Jeff's Comments: Zincite is brittle, so be careful not to shock the stone while cutting and use fine laps for roughing in.

Design Links: 4-Way Stop - This is great for saturated rough if you have a piece that will work in the shape.

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