Explanation of Chalcedony
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 chrysoplace.
It’s said “Gyoku zui”, in Japanese.
