SEASON TYPE:summer type, spring type, autumn type.

​

Composition: CaO, MgO, Mn2O3, FeO, Si02_Manganese-781994bath.

​

Origin:Spain, Sweden, Germany, Mexico, Brazil, United States, Russia, South Africa, Australia, Canada, Finland, Japan, Madagascar, Mexico, Tanzania, India.

​

The hardness on the scale of Mohs 7.5.