Yufu Topaz <Niigata Prefecture> [Famous Stones of Japan]
YUFUOGYOKU
oil cloth yellow ball
One of the types of Sado Akaishi is "Yufu Kogyoku."
Golden stones have been highly prized.
It is a mineral formed when a large amount of iron oxide is bonded to quartz under high temperature and pressure.
Yufu Topaz is mined in the Kokura area of Sado City and is now protected, with the amount in circulation drastically reduced.
SADO YUFUOGYOKU is a type of Sado Akaishi that is mined in Sado City, Niigata Prefecture. This calm color is caused by a large amount of iron oxide bonding with quartz under high temperature and pressure, and this golden-colored stone is a very rare color even among Sado Akaishi. In addition, since mining itself is currently prohibited, it is a stone that is very difficult to obtain.
| Origin | Niigata Prefecture |
|---|---|
| meaning | vitality, mental strength, insight |
| Mineral Classification | oxide minerals |
| chemical composition | SiO₂ |
| Crystalline | trigonal system, hexagonal system |
| cleavage | none |
| Mohs hardness | 6.0–7.0 |
| gloss | Glass gloss |
| color | Red, brown, white, black, yellow, orange |
| specific gravity | 2.6 to 2.9 |
