Studtite, chemical formula [(UO2)O2(H2O)2]·2(H2O)[2] or UO4·4(H2O),[3] is a secondary uranium mineral containing peroxide formed by the alpha-radiolysis of water during formation.

The mineral was named for Franz Edward Studt, an English prospector and geologist who was working for the Belgians.

When exposed to air studtite converts over a short time to the metastudtite UO4·2(H2O) form.

[7] It has also been reported that studtite has since formed on the corium lavas that were created during the course of the Chernobyl nuclear plant accident.

[7] Due to insufficient information about these minerals it is unknown if they will make radioactive wastes more or less stable, but the presence of studtite and metastudtite provides a pathway for mobilizing insoluble U(IV) from the corroding fuel surface into soluble uranyl species.