Yellow crystal aggregates of the very rare uranium-niobium-tantalum mineral liandratite associated to black columbite-(Mn). From Mica Lode Mine, Eight Mile Park Pegmatite, Fremont County, Colorado, United States of America. Ex. Erich Laskowski collection — Photo: David Hospital · CC BY-SA 4.0
Liandratite
Liandratite is an IMA-recognized mineral species in the oxides & hydroxide class, with the chemical formula U⁶⁺Nb₂O₈.
It crystallizes in the hexagonal crystal system (space group P-31m).
Key properties: Mohs hardness 3.5; specific gravity 7; Pale yellow streak; Glassy luster.
IMA symbol Lia, IMA status: approved, named in 1975.
Found in a zoned pegmatite in amphibolite-grade gneiss, as an oxidized crust over petscheckite.
It is found associated with Petscheckite, columbite, pyrochlore, strüverite, monazite, ilmenite, garnet, tourmaline, beryl, quartz, feldspar.
The mineral was named to honor Professor George Liandrat, of Samoëns, France, who prospected in Madagascar.