Johnbaumite and Calcite - from the Jakobsberg Mine, Nordmark, Sweden
Contributed by: Mark Cole
Date: Apr 7th, 2026
Locality: Jakobsberg Mine, Jakobsberg ore field, Nordmark mining district, Filipstad, Värmland County, Sweden (See on Mindat)
Description:
Johnbaumite is only found in a couple of places around the world - Franklin, Sweden, and Russia (maybe Japan???). I visited Sweden in 2014 with a small group of fellow collectors. People ask me, "What were the nicest pieces from this trip?" - I have to say the very few pieces of johnbaumite we found. We worked really hard and only came across a couple of specimens for our entire group.
Johnbaumite fluoresces medium pinkish orange under SW UV. A member of the apatite group, it is a very rare mineral, part of a metamorphic skarn assemblage in a metamorphosed stratiform zinc orebody. Notable occurrences: Franklin and Sterling Hill, Ogdensburg, Sussex Co., New Jersey, USA. Russia, at undisclosed deposits in the Ural Mountains and Siberia. Langban, Varmland, Sweden.
The name honors John L. Baum (1916–2011), Hamburg, New Jersey, USA, Curator of the Franklin Mineral Museum, and collector of the first specimen containing the mineral.
Originally posted by Mark Cole on Nature's Rainbows in 2016.
Summary of luminescence responses:
Johnbaumite (Mindat) (RRUFF)
- Fluorescence under Shortwave (254nm Lamp/Mercury) UV light: Purple
- Fluorescence under Shortwave (254nm Lamp/Mercury) UV light: Red