It crystallizes in the orthorhombic system in translucent lathlike, elongated, commonly radiating in fibrous, and in pulverulent, earthy to very fine-grained dense masses.

It has been reported in the Democratic Republic of Congo, the Northern Territory of Australia and a variety of locations worldwide.

[3] It occurs as a secondary mineral as a weathering product of uraninite.

In addition to uraninite it occurs associated with the rare minerals becquerelite, masuyite, schoepite, kasolite, curite, boltwoodite, vandendriesscheite, billietite, metatorbernite, fourmarierite, studtite and sklodowskite.

[2] It forms under acidic to neutral pH and is the only known mineral that contains only uranyl and carbonate.