Mineralpedia Details for Umbozerite
Named after Lake Umbozero in the Kola Peninsula of Russia near where Umbozeroite finds its type locality at the Umbozero mine. Occuring only in Russia, it is found “in pneumatolytic-hydrothermal veins cutting alkalic rocks in the upper part of a differentiated alkalic massif.” Umbozeroite is radioactive.
Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/umbozerite.pdf
Umbozerite from Lovozero Massif, Kola Peninsula, Russia
Umbozerite from Pegmatite #60, Karnasurt Mt., Lovozero Massif, Kola Peninsula, Russia
Radiating acicular sprays to 1cm embedded in Ussingite matrix. Because of the Thorium content of this mineral it is typically or always found as metamict product. This mineral is found in only a handful of localities all in alkalic deposits as reflected by the Ussingite matrix.