Opal-AN and Chalcedony - Sardinia, Italy

Contributed by: Mark Cole
Date: Apr 7th, 2026
Locality: Calasetta, South Sardinia Province, Sardinia, Italy (See on Mindat)

Description:
Originally posted by Mark Cole on Nature's Rainbows in 2016.

Fluorescence under shortwave UV light.

Normal light.

Summary of luminescence responses:

Chalcedony (Mindat) (RRUFF)

• Fluorescence under Shortwave (254nm Lamp/Mercury) UV light: White

• Fluorescence under Shortwave (254nm Lamp/Mercury) UV light: Green