URANIUM SUPPLIES

Greymouth Evening Star, 19 September 1945, Page 6

URANIUM SUPPLIES

CANADA IN THE LEAD The emergence of the atomic bomb will undoubtedly stimulate the search for uranium, the principal metal used in the production of the new weapon, wrote the London “Times” before Japan’s capitulation. Canada leads the Empire and the world in the supply of this metal. The story of uranium is really the story of radium, of which it is a byproduct. Both are derived mainly from pitchblende, but before the war broke ■ out little interest was taken in uranium, the sole desire being to increase the quantity of radium. Relatively, uranium was found to be of little use commercially because of its prohibitive cost, though it was employed for colouring ceramics and for removing undesirable properties in steel, thereby increasing its toughness, and it had also been added to copper to yield a corrosion-resistent alloy which was an excellent conductor of heat and electricity. Although at least 100 minerals are .thought to contain uranium, the only important uranium ‘ore, apart from, pitchblende, is carnotite, which is obtained in Colorado. It was from this source that the United States created a virtual monopoly of the radium market until in 1923 the great deposits of pitchblende in the Belgian Congo were worked and became the centre of the world market in radium.. Then came the great pitchblende discoveries at Great Bar Lake in Canada, which brought down still further the price of radium. America has vast deposits of carnotite, which- are quite rich in uranium, but radium-uranium minerals occur all over the world. One of the earliest of these was discovered on Germany ,s doorstep—at Joachimsthal, in Bohemia; it was in the pitchblende here that radium was first discovered by Professor and Mme. Curie. There are also deposits of pitchblende in Australia, South Africa, and probably in Russia. Thus, in the aggregate, there .is a good deal of it throughout the world, though it is not easily mined. In 1938 the United States produced 4290 short tons of carnotite ore, the radium content of which was 7821 milligrammes, and the uranium content 51,7051 b. In pitchblende, only about one part of radium is present to 3,000,000 parts of uranium, so that for every gramme of radium produced,, nearly three tons of uranium are obtained. SKYROCKETING IMPORTS

The Canadian production of pitchblende was very much higher, the estimated output for 1938 being 75 grammes of radium and 800,0001 b. of uranium salts. The United States imported 376,7081 b of uranium oxide and salts in the same year, 1,439,3241 b in 1939, and though the amount Jell to 240,1991 b in 1940, it is significant that the amount of uranium orc imported in that year increased to 2,500,0001 b. It has to be remembered that Uranium 235, reported to be used in the production of the atomic bomb, forms only a minute proportion of uranium salts—one authority gives it as 0.1 per rent. The Year Book of the Unitea States Bureau of Mines, published in 1941 and covering the preceding year, indicates the attention which was then being given io U-235. There it is pointed oufthat when U-235 is hit by ■a neutron that enters into its nucleus the atomic weight becomes 236, which is an exploding atom that .splits easily. Merely by adding waler, it is stated, energy can be released, and when all this water is converted into steam the •orocess stops unless more water is .supplied, making the energy-liberat-ing process automatic and self-regu-.lcit Great Britain’s contribution to the .supply of pitchblende has always been small, though it was from the South Terrace pitchblende mine, Cornwall, that Dr. Roehm, the French chemist, gained the experience that enabled him to become head of the great refinery at Port Hope, in Canada.