Amethyst round cut loose faceted for sale 5 cts 5 to 7mm s198

 We sell rough and cut gemstones, offering a wide range of rough gemstones for specimen-cabbing-facet and beautiful cut stones ready for your mount..Either for a new piece of jewelry or replacing a stone in an existing piece of jewelry.We offer thousands of lots, all with individual photos, what you see in the photo is what you will receive. Tommysrocks, an internet only business since 2002, giving our internet customers 100% of our attention.

Mohs hardness: 7

Refractive index: 1.544-1.553

Critical angle: 40°

Specific gravity: 2.63-2.65

Cleavage: None

Fracture: Conchoidal, brittle.

Dispersion: Medium (.013)

Heat sensitivity: Low

Pleochroism: Amethyst: very weak (purple to grayish purple); Natural citrine: weak (yellow to light-yellow); Prasiolite: very weak (light-green to paler green); Rock crystal: colorless, no dichroism; Rose quartz: weak (pink to paler pink); Natural dark smoky: definite (brown to reddish-brown).

Birefringence (double refraction): Weak (.009)

Crystal structure: Hexagonal

Cutting: Quartz cuts easily.  Pre-polishing with 1200 Nubond or 3000 standard lap will make polishing much quicker and more enjoyable.

Polishing: Cerium oxide on most common polishing laps.