Calcite Crystals with Internal Phantoms - Sweetwater Mine, Reynolds County, Missouri

Contributed by: Chris Clemens
minID: 3D5-F7W
Date: May 21st, 2026
Locality: Sweetwater Mine, Ellington, Reynolds County, Missouri, USA (See on Mindat)
Size: 9.2 x 6.4 x 15.5 cm
Weight: 711 g

Description:
This spectacular fluorescent specimen, from a classic midwestern location, consists of a large cluster of light tan/yellow colored, waxy textured, scalenohedral calcite crystals on a dolomite matrix with minor chalcopyrite. Each crystal shows a distinct, dark, internal phantom. This piece is from the Sweetwater Mine, Ellington, Viburnum Trend District, Reynolds Co., Missouri. As seen in the photographs, the calcite shows a beautiful bright pink, fluorescent response under midwave UV (302nm). Interestingly, the calcite is only dimly fluorescent red under shortwave and longwave UV (not shown).

Originally posted by Chris Clemens on Nature's Rainbows in 2016.

Fluorescence under midwave UV light.

Normal light.

Summary of luminescence responses:

Calcite (Mindat) (RRUFF)

• Fluorescence under Midwave (305nm Lamp/Mercury) UV light: Pink