
A mineral made of extremely fine granular or fibrous quartz. It may also contain a mineral called moganite, which is polymorphic to quartz. There are various colors such as colorless, red, orange (daidai), green, yellow, and black, and there are various variant names. Some are used as decorative stones such as agate, carnelian, and … Read More

Topaz, the birthstone for the month of November, is a beautiful transparent orange-yellow, and its color has been compared to sherry. It is a typical yellow gemstone, and perhaps because of this, jewelry with a yellow color is often given the pseudonym “topaz. In fact, topaz is a gemstone with a great variety of … Read More

The hardest gem diamond on earth. Because of its hardness, the meaning of “connecting hard bonds” is included. Japanese says “Kon go seki”.

Japanese calls Kuro-Tan-Paku-Seki. Black Opal is a greenish type of opal with black mottling and gold flecks. Usually found in ancient hot springs, the gem is usually tumbled smooth and cut cabochon.