“Gummite” is the name given to a mixture of uraninite and secondary uranium minerals of variable composition.

This mixture is composed of uraninite remnants mixed with boltwoodite, clarkeite, curite, kasolite, soddyite, and uranophane.

Sometimes the material has the appearance and consistency of rubber, and the name comes from this: “Gummi” means rubber in German. There are a dozen different names in German for this mixture.

It is associated with zircon, fluorapatite, and several radioactive minerals: uraninite, uranophane, autunite, cyrtolite, meta-autunite, and pitchblende.

Gummite and its associated minerals are radioactive, and their handling must follow compatible safety procedures! Any unknown ore, but especially if it shows yellow and green minerals, must undergo a radioactivity test!