Sphalerite Facet / Faceting Information
Practical tips on Sphalerite Facet / Faceting Information. Covers Sphalerite Facet / Faceting Information related issues, news, research, tips, and guide.
Sphalerite Facet / Faceting Information
Sphalerite
Color: Green, brown, yellow, red, orange and colorless
Moh's Hardness: 3.5-4
Refractive Index: 2.268-2.371
Critical Angle: 26.26°
Specific Gravity: 4.08-4.10
Cleavage: Perfect in 6 directions
Fracture: Uneven, brittle
Dispersion: .156
Heat Sensitivity: Moderate
Birefringence (double refraction): None
Crystal Structure: Cubic, isometric
Treatments: Generally none
What I prefer to polishing with: Alumina oxide on tin or wax lap
Jeff's Comments: Faceting grade material is not common and seldom very big. Orient the stone to avoid cleavage planes on the table and use a fine lap for cutting. Some facets may take hand lapping to get them cut and polished. Finished stones are quite stunning.
Design Notes: About any Zircon design will work well.
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.
Related Articles
Andalusite Faceting Information
Goshenite Facet / Faceting Information
Danburite Facet / Faceting Information
Pyrope (Rhodolite) Garnet Faceting
Latest Articles
21 Pink Gemstones (How Many Do You Know?)
How Does Topaz Form?
Sphene (Titanite) Value, Price, and Jewelry Information
Citrine Buying Guide
Never Stop Learning
When you join the IGS community, you get trusted diamond & gemstone information when you need it.
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!