Uranium ore support a neutron-mediated chain reaction). Uranium, thorium, and potassium are the main elements contributing to natural terrestrial radioactivity. Uranium has the highest atomic weight of the naturally occurring elements and is approximately 70% denser than lead, but not as dense as tungsten, gold, platinum, iridium, or osmium. It is always found combined with other elements. Along with all elements having atomic weights higher than that of iron, it is only naturally formed in supernova explosions. The primary uranium ore mineral is uraninite (UO) (previously known as pitchblende). A range of other uranium minerals can be found in various deposits. These
Mineral industry of Colombia Mineral industry of Colombia Mineral industry of Colombia refers to the extraction of valuable minerals or other geological materials in Colombia. Colombia is well-endowed with minerals and energy resources. It has the largest coal reserves in Latin America, and is second to Brazil in hydroelectric potential. Estimates of petroleum reserves in 1995 were . Colombia also possesses significant amounts of nickel and gold. Other important metals included platinum and silver, which were extracted in much smaller quantities. Colombia also produces copper, small amounts of iron ore, and bauxite. Nonmetallic mined minerals include salt, limestone, sulfur, gypsum, dolomite, barite, feldspar, clay,