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"More powerful than uranium"; used by men from the Moon. Metal X (Rovolon) E. E. Smith's SkyLark series: An element discovered that facilitates conversion of the energy in metals (copper or uranium) and uses it as a propulsive or attractive force. The Norlaminians had already discovered this metal and named it Rovolon.
Autunite (hydrated calcium uranyl phosphate), with formula Ca(UO 2) 2 (PO 4) 2 ·10–12H 2 O, is a yellow-greenish fluorescent phosphate mineral with a hardness of 2– 2 + 1 ⁄ 2. [4] [5] Autunite crystallizes in the orthorhombic system and often occurs as tabular square crystals, commonly in small crusts or in fan-like masses.
Uranium is a silvery-gray, weakly radioactive metallic chemical element.It has the chemical symbol U and atomic number 92. The most common isotopes in natural uranium are 238 U (99.274%) and 235 U (0.711%).
The extremely rare elements technetium and promethium can be found in uraninite in very small quantities (about 200 pg/kg and 4 fg/kg respectively), produced by the spontaneous fission of uranium-238. Francium can also be found in uraninite at 1 francium atom for every 1 × 10 18 uranium atoms in the ore as a result from the decay of actinium.
Carnotite is a bright greenish-yellow mineral that occurs typically as crusts and flakes in sandstones. Amounts as low as one percent will color the sandstone a bright yellow. The high uranium content makes carnotite an important uranium ore. It is a secondary vanadium and uranium mineral usually found in sedimentary rocks in arid climates.
Actinium is found only in traces in uranium and thorium ores as the isotope 227 Ac, which decays with a half-life of 21.772 years, predominantly emitting beta and sometimes alpha particles, and 228 Ac, which is beta active with a half-life of 6.15 hours.
Uranium is a chemical element with the symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Uranium radioactively decays, usually by emitting an alpha particle.
The central uranium site of coffinite is surrounded by eight SiO 4 tetrahedra. The lattice dimensions of naturally-occurring and synthetic coffinite are similar, with a naturally-occurring sample from Arrowhead Mine, Mesa County, Colorado having a=6.93kx, c=6.30kx, and a sample synthesized by Hoekstra and Fuchs having a=6.977kx and c=6.307kx.