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sphalerite
Karatz GemMagazine
" Sphalerite "
Sphalerite has a dispersion rate that is approximately 4 times that of diamond, and its main feature is that it emits a strong glare in the light.
Due to its brittle nature, this gemstone must be handled with care to avoid strong impacts.
| English name | Sphalerite |
| Japanese name | Sphalerite |
| crystal system | equiaxed crystal system |
| chemical composition formula | ZnS |
| mohs hardness | 3.5 – 4 |
| specific gravity | 3.90 - 4.10 |
| refractive index | 2.36 - 2.43 |
| luster | Resin luster ~ Kongo luster |
Usually it is black or brown in color, but gem-quality stones are said to often have yellow, honey brown, orange, green, and red colors.
●Things with deep and vivid colors ●Things with high transparency without inclusions, scratches, or chips ●Things with beautiful cuts ●Things that are large in size ●Things with strong fire and beauty are considered to be more valuable.
Also, green items become more valuable due to their rarity.
The main sources of gem-quality sphalerite are Spain, Mexico, the United States, and Canada.
In Japan, it has been found in the Ota Mine in Aomori Prefecture, the Sayama Mine in Akita Prefecture, and the Kamioka Mine in Gifu Prefecture.
There are various theories about the origin of the name sphalerite, but one theory is that it was named from the Greek word "sphaleros" (unreliable) because its appearance could easily be confused with other minerals.