Discovered by M. H. Klaproth at Berlin, German; isolated in 1841 by E. M. Pleigot at Paris, France
Remarks
Radioactive silvery metal. malleable, ductile, and tarnishes in air. Attacked by steam and acids but not by alkalis. Used as nuclear fuel and in nuclear weapons.
Diagnostic tests:
Uranium is usually detected by radioactivity (due, in part, to the
daughter elements such as radium). Thorium is also naturally radioactive;
however, many uranium minerals are generally yellow or green and
fluorescent.
With a borax bead
test in the oxidizing flame, the bead is
yellow to brownish red color while hot and is colorless to yellow when
cold. This test is very similar to iron.
The Na2(NH4)(PO4) bead
test for uranium is a much better test, under oxidizing conditions the
bead is clear yellow (hot)
yielding slightly greenish yellow on cooling. In the reducing flame, it becomes
a fine green color when hot or cold.
References
Emsley, J., 1991; THE ELEMENTS : Sec. Ed.,
Clarendon Press, Oxford, 251 p.
(* - Mineral Name Is Not IMA Approved)
(! - New Dana classification added or changed from Danas New Mineralogy)
(? - IMA Discredited Mineral Species Name)
There are 249 minerals with U in the Mineralogy Database.