Supply of Uranium (updated August 2012) - Uranium is a
relatively common metal, found in rocks and seawater. Economic
concentrations of it are not uncommon. - Its availability to
supply world energy needs is great both geologically and because
of the technology for its use. - Quantities of mineral resources
are greater than commonly perceived. - The world's known uranium
resources increased 15% in two years to 2007 due to increased
mineral exploration. Uranium is a relatively common element in
the crust of the Earth (very much more than in the mantle). It
is a metal approximately as common as tin or zinc, and it is a
constituent of most rocks and even of the sea. Some typical
concentrations are: (ppm = parts per million). | Very high-grade
ore (Canada) - 20% U ||200,000 ppm U |High-grade ore - 2% U,
||20,000 ppm U |Low-grade ore - 0.1% U, ||1,000 ppm U | Very
low-grade ore* (Namibia) - 0.01% U ||100 ppm U ||3-5 ppm U ||2-3
ppm U |Earth's continental crust (av) ||2.8 ppm U ||0.003 ppm U
* Where uranium is at l