Calcite and unknowns - Black Wonder District, California
Contributed by: FMS Admin
Date: May 24th, 2026
Locality: Black Wonder Mining District, Santa Clara County, California, USA (See on Mindat)
Size: 3 inches
Description:
This one is a bit unusual for much of the material collected from along the roads in the Black Wonder District in the Diablo Range in Northern California. It appears to have small cubes of calcite in portions of the specimen. Very little is known about the makeup of this material and similar material is under testing to determine what is really here. For now, it is calcite and unknowns.
Originally posted by Fire Viper on Nature's Rainbows in 2017.
Summary of luminescence responses:
Calcite (Mindat) (RRUFF)
- Fluorescence under Longwave (365nm Lamp/Mercury) UV light: Orange
- Fluorescence under Longwave (365nm Lamp/Mercury) UV light: Blue