Class : -
    Subclass : -
    Crystal system : -
    Chemistry : -
    Rarity : Quite common

Like garnierite or bauxite, gummite is not a mineral but a collection of minerals. The term gummite in fact designates secondary cryptocrystalline uranium minerals, generally powdery, formed in a hot or temperate climate by oxidation of uraninite (often in its concretionary pitchblende facies). It was named thus in allusion to its resin or gum appearance. These are essentially oxides and silicates of uranium associated with various metals. Almost all gummites retain the characteristic structures of uraninites and especially pitchblendes which they epigenize. The yellow gummites, the most common, are largely composed of uranotile (or uranophane), the orange gummites (sometimes red) of curite, billiétite or ianthinite. Black gummites correspond to altered rocks colored black by small quantities of residual UO₂, surviving the transformation into UO₃ during the oxidation of pitchblende. Gummites constitute a significant part of the uranium ore in the oxidation zones of the deposits.

Main photo : Gummite from Luiswishi Mine, Kawama, Haut-Katanga, DR Congo © Paul de Bondt

No fakes recorded for this mineral species.