Willemite Crystal on Calcite Matrix, Sterling Mine, Sterling Hill, New Jersey

Contributed by: Chris Clemens
minID: L81-QA0
Date: Apr 19th, 2026
Locality: Sterling Mine, Sterling Hill, Ogdensburg, Sussex County, New Jersey, USA (See on Mindat)
Size: 76 x 48 x 86 mm
Weight: 405 g

Description:
A large, well-formed, red/brown willemite crystal sits on top of a matrix of white calcite, from the Sterling Mine, Sterling Hill, Ogdensburg, New Jersey. The willemite fluoresces bright green and the calcite matrix shows a bright red/orange response under shortwave UV (254 nm). This specimen is also moderately fluorescent under longwave UV (365 nm). The willemite shows a more subdued green response and the calcite fluoresces a magenta color.

Originally posted by Chris Clemens on Nature's Rainbows in 2020.

Fluorescence under shortwave UV light.

Fluorescence under longwave UV light.

Normal light.

Summary of luminescence responses:

Willemite (Mindat) (RRUFF)

• Fluorescence under Longwave (365nm LED) UV light: Green
• Fluorescence under Shortwave (254nm Lamp/Mercury) UV light: Green

• Fluorescence under Longwave (365nm LED) UV light: Pink
• Fluorescence under Shortwave (254nm Lamp/Mercury) UV light: Red