Red Lightning Calcite and Aragonite - Promontory Point, Utah
Contributed by: FMS Admin
Date: May 26th, 2026
Locality: Promontory Point, Promontory Mining District, Promontory Mountains, Box Elder County, Utah, USA (See on Mindat)
Description:
An interesting little specimen from Promontory Point in Utah. The red fluorescing calcite is like a circular bolt of lightning. The aragonite glows bluish white in shortwave, day old cream in midwave, and off white in long wave. It's also highly phosphorescent (not shown).
Originally posted by Fire Viper on Nature's Rainbows in 2016.
Summary of luminescence responses:
Aragonite (Mindat) (RRUFF)
- Fluorescence under Shortwave (254nm Lamp/Mercury) UV light: White
- Fluorescence under Shortwave (254nm Lamp/Mercury) UV light: Red