Granite and syenite pegmatites. Colloform crusts in high temperature hydrothermal veins. In quartz-pebble conglomerates.
IMA Status:
Valid Species (Pre-IMA) 1772
Locality:
Southern parts of the Canadian Precambrian Shield, Bancroft, Ontario. New Hampshire, USA. Transvaal gold-bearing conglomerates. Link to MinDat.org Location Data.
Name Origin:
From its elemental composition containing uranium.
Chemical Formula: 