Clinohedrite, Charlesite, and Roeblingite – Franklin, New Jersey

Contributed by: FMS Admin
Date: Mar 9th, 2026
Locality: Franklin Mine, Franklin, Sussex County, New Jersey, USA (See on Mindat)
Size: 5 x 4 x 6.5 cm

Description:
A fragment of highly altered, granular franklinite-calcite-hendricksite ore bearing a hydrothermal alteration crust of several minerals: myriad gray to slightly amethystine crystals of clinohedrite, numerous white tiny crystals of charlesite, and roeblingite (pale yellowish tan mineral at upper left, dimly fluorescent except near lower contact).
Note that the colors mentioned refer to the daylight image. In the fluorescent photo (SW), pale blue is charlesite, red is roeblingite, orange is clinohedrite. Tiny green specks are willemite "dust".

Originally posted by Earl Verbeek on Nature's Rainbows.

Fluorescence under shortwave UV light.

Normal light.

Summary of luminescence responses:

Charlesite (Mindat) (RRUFF)

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

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

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