Sphalerite and Willemite

Contributed by: Axel Emmermann
Date: Jan 23rd, 2025
Locality: Franklin Mining District, Sussex County, New Jersey, USA (See on Mindat)

Description:
Sphalerite with willemite. The sphalerite has a nice phosphorescence, which helps to distinguish it from calcite. SW and MW-UV combined.

Fluorescence under shortwave and midwave UV light.

Normal light.

Summary of luminescence responses:

Sphalerite (Mindat) (RRUFF)

• Fluorescence under Midwave (305nm Lamp/Mercury) UV light: Orange
• Afterglow after exposure to Midwave (305nm Lamp/Mercury) UV light: Orange

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