Mineralpedia Details for Dumontite
Named after Belgian geologist Andre Hubert Dumont. Dumontite is a rare mineral that occurs in the Democratic Republic of the Congo, the United States, Australia, as well as at newer localities in Italy, France, Germany, Austria, Slovenia, and Tajikistan. It occurs in pockets of tobernite in oxidized uranium deposits at its type locality in the Shinkolobwe mine in the Democratic Republic of the Congo. Dumontite can fluoresce pale green under ultraviolet light and is quite radioactive.
Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/dumontite.pdf
Dumontite from Musonoi mine, Kolwezi, Shaba Cu belt, Democratic Republic of Congo
Bright yellow-orange rosettes to 0.1mm composed of platy crystals on Torbernite.