Fluorescent Ruby from Tanzania

Contributed by: FMS Admin
minID: 3F5-LG0
Date: May 11th, 2026
Locality: Mundarara Mine, Longido District, Arusha Region, Tanzania (See on Mindat)
Size: 6.3 x 2.8 x 7.5 cm

Description:
Shown here is a pretty nice specimen of corundum var. ruby from the Mundarara Mine, Longido District, Arusha Region, Tanzania. Its fluorescence is not very bright, but it is a beautiful, deep saturated red. Just bright enough for a display, if placed closer to the lamp.

Originally posted by Frédéric Messier Leroux on Nature's Rainbows in 2022.

Fluorescence under longwave UV light.

Normal light.

Summary of luminescence responses:

Corundum var. Ruby (Mindat) (RRUFF)

• Fluorescence under Longwave (365nm LED) UV light: Red