Ametrine Facet / Faceting Information


Source on Ametrine gemstones and various information on the cuts and polishes. With guides that cover great information on Ametrine facet.

0

Ametrine Facet / Faceting Information

Ametrine (Quartz)

Ice cut in Ametrine/ametrine facet

Color: Amethyst/Citrine mix - purple, violet to red-violet, blue/purple with yellow/gold orange
Moh's Hardness: 7
Refractive Index: 1.544-1.553
Critical Angle: 40.49°
Specific Gravity: 2.63-2.65
Cleavage: None
Fracture: Conchoidal
Dispersion: .013
Heat Sensitivity: Can be... but is usually not a problem
Dichroism: very weak
Birefringence (double refraction): Weak (.009)
Crystal structure: Hexagonal

Treatments: Generally none.

What I prefer to polishing with: Cerium oxide with a Spectra Ultralap.

Jeff's Comments: Cuts and polishes like any other Quartz, usually no problems... I like to use a 1200 Nu Bond lap for pre-polish, it makes the polishing stage faster and easier. Watch for stress flaws around the color zone changes. Some very interesting effects can be created by orientating the color zones differently.

Design Notes: About any Quartz design will work well. As the rough gets more saturated, I prefer cheacker boards and bar cuts.

Design Links: 4-Way Stop - This is great for saturated rough if you have a piece that will work in the shape...
Be Still My Heart - Good in about any Quartz
CheckMate - Neat in medium color Quartz
Light House - Nice in any Quartz
Utopia - Classic Barion pear


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.

Never Stop Learning

When you join the IGS community, you get trusted diamond & gemstone information when you need it.

Become a Member

Get Gemology Insights

Get started with the International Gem Society’s free guide to gemstone identification. Join our weekly newsletter & get a free copy of the Gem ID Checklist!