Tsumcorite is a rare hydrated lead arsenate mineral that was discovered in 1971, and reported by Geier, Kautz and Muller.

They occur in radiating sheaves and spherulites, and as fibrous crusts or earthy and powdery material.

[5] Tsumcorite is yellow-brown, red-brown or orange in color, and it is one of the few minerals that have a yellow streak (orpiment and crocoite are two others).

[4] Tsumcorite is a rare secondary mineral in the oxidized zone of some arsenic-bearing hydrothermal lead-zinc deposits.

[5] At the Kintore Open Cut, Broken Hill, Australia it occurs with segnitite, beudantite, carminite and mawbyite.