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Colour:Orange, yellow, ...Hardness:2½ - 5
Name:In allusion to the gum-like or rubber-like (rubber = gummi in German) appearance of some early material.
A Mixture Of:Boltwoodite, Clarkeite, Curite, Kasolite, Soddyite, Uraninite, Uranophane

A mixture of uraninite and secondary uranium minerals of variable composition.

Classification of Gummite

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Physical Properties of Gummite

Lustre:Vitreous, Waxy, Greasy, Dull
Diaphaneity (Transparency):Translucent
Colour:Orange, yellow, orange-red, red-brown, brown-black, black
Streak:Yellow, brownish, olive-green
Hardness (Mohs):2½ - 5
Cleavage:None Observed
Fracture:Irregular/Uneven, Conchoidal
Density (measured):3.9 - 6.4 g/cm3

Other Names for Gummite

Other Languages:
Fester Uranocker
Lichtes Uranpecherz
Uranisches Gummi-Erz
Uranisches Pittin-Erz

Other Information

Health Warning:Contains uranium - always wash hands after handling. Avoid inhaling dust when handling or breaking. Never lick or ingest. Avoid prolonged exposure in proximity of the body. Store away from inhabited areas.

References for Gummite

Reference List:

- +
Breithaupt (1847): 903 (as urangummi).

Palache, Charles, Harry Berman & Clifford Frondel (1944), The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana Yale University 1837-1892, Volume I: Elements, Sulfides, Sulfosalts, Oxides. John Wiley and Sons, Inc., New York. 7th edition, revised and enlarged: 622-624.

Frondel, C. (1956) The mineralogical composition of gummite. American Mineralogist: 41: 539-568.

Internet Links for Gummite

Search Engines:
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  • Fabre Minerals - search for Gummite specimens
  • Search for Gummite on Well-Arranged Molecules
  • Fine Minerals from Weinrich Minerals, Inc.
  • Localities for Gummite

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