Atomic Energy

on the World Today

UNTIL 1940 about the only use for uranium was as a coloring agent in the manufacture of ceramics and glass — notably the glass used in amber signal lenses — and it had been used in this fashion for about a hundred years. A still more minor use was in the making of certain alloy steels.

But today uranium is the sole source of atomic energy. This Cinderella among the world’s metals is a thousand times as plentiful as gold, a hundred times as plentiful as silver, and nearly as plentiful as lead or zinc. Unfortunately, however, it is spread very thin, and workable deposits are few.

The hunt for exploitable concentrations of uranium constitutes the mining rush of 1949 — a rush fully as intense as that of 1849, but different in many critical respects. As the hunt proceeds, mining companies are bearing in mind Commissioner Sumner T. Pike’s reminder that many common minerals are getting harder to find. This fact, in combination with advances in metallurgy and with changing requirements of various industries, is forcing a development of metallic elements which never before were of noteworthy economic value.

Citing the shortening of domestic supplies of copper, lead, zinc, and other metals, the probable continued importation of raw aluminum ore, and the inroads that have been made upon our known resources of high-grade iron ore, Commissioner Pike has pointed out that “it seems very possible that we are now seeing the beginning of a major rearrangement in the economic values of various metals. Some of these have been familiar and cheap and now are becoming scarce and dear. Others have been practically unknown but are now coming well within the spectrum of economic value. The case of uranium during the last ten years is of course the spectacular instance. The American mining industry will be wise if it keeps its eyes closely upon other candidates.”

Uranium from pitchblende

It is a legitimate assumption that the crustiest, desert rat and the suavest mining engineer alike, as the hunt goes on, are keeping their eyes alert for indications of pitchblende, for since the middle of the nineteenth century this has been by far the most important uranium mineral, Consisting essentially of uranium oxide, it is the principal component of nearly all high-grade uranium ore. Most of the slocks of uranium and associated radium that have been produced in the world have come from pitchblende veins, of which there are two main types.

The first of these consists of veins mined primarily for lead, zinc, copper, gold, and silver, as in Gilpin and Boulder counties, Colorado, where the pitchblende shows as narrow streaks and patches. The yield from deposits of this sort has been slight. It is veins containing cobalt and nickel minerals, in addition to other base metals and lesser amounts of gold and silver, that have contributed the most to the world stocks of uranium, The famed radium-uranium mines of Joachimsthal, Czechoslovakia; Eldorado, Canada; and Shinkolobwc, Belgian Congo — the three most productive in the world — are working veins of this second type.

Two other types of uranium deposits, not yet clearly classifiable, will besought by the prospecting eye. The vanadium-uranium ores, carnotite and roscoelite, which occur on the Colorado plateau and in lesser amounts in other parts of the world, are one. They are found as small tabular or lens-shaped deposits in sandstones and conglomerates, often completely replacing fossil logs and twigs — a fact which suggests that carbonaceous material is a precipitant for uranium.

The second type of vaguely understood deposit occurs in the Witwatersrand gold-bearing conglomerates of South Africa. The gold ores of the Witwatersrand reefs have for years been known to contain small amounts of uraninite — a uranium oxide — but investigation of the possibility of uranium as a by-product from this source waited on the present demand. The Atomic Energy Commission has stated that informal discussions by the United States and the United Kingdom with the Union of South Africa have for years been confined to the problems involved in producing uranium contained in the South African gold ores. “ Further discussions are envisaged,”ihe Commission continues, “and while no date has been set it is expected that representatives of the United States and the United Kingdom will visit South Africa, on the imitation of that government, to continue discussions concerning the eventual production of uranium from the gold-bearing ores of South Africa.”From such new sources, it is hoped, will come increased supplies of ore heavily laden with uranium oxide, U3O8.

Convening ore to energy

After delivery of the ore and the first processing for grinding, analysis, and assay, ihe arduous business begins, with refinement to “brown oxide,”UO2, of extreme purity, conversion of the brown oxide to “green salt” (uranium tetrafluoride, UF4), and thereafter, conversion of the green salt either to uranium metal or to uranium hexafluoride, UF6.

At Hanford, Washington, uranium metal is turned into the man-made fissionable element plutonium. At Oak Ridge, ’Tennessee, uranium hexafluoride, which upon heating becomes a gas, is subjected to the gaseous diffusion process which separates the plentiful isotope Cranium 238 from the precious fissionable isotope Uranium 235 — at a rate of about a dozen pounds to the ton of concentrated metal.

In this process there are many possibilities of loss or misplacement such as stir up investigations. It is very difficult to arrive at an accurate inventory of material in gaseous, liquid, and solid forms. Furthermore, the manufacturing process is the most intricate in history, and many operations must for safety’s sake be performed under remote control.

An idea of the complexities may be bad from the fact that the porous barriers through which uranium gas is diffused in the separation plant K-25 at Oak Ridge must contain billions of holes per square inch — holes only a few ten-millionths of an inch in diameter. These porous barriers must be very thin, and yet must stand up under substantial pressure. And the total area of such barrier material at K-25 is measured in square miles.

Uranium detectors

As ore hunters seek raw materials, they have new aids their predecessors would not recognize. With the exception of pitchblende, uranium ores fluoresce under ultraviolet light, so that the beelike buzz of special lamps that make “black light” is an undertone of the search. A staccato accompaniment is the chattering click of Geiger counters, devices somewhat similar to a small battery-operated radio, which register radiation from radioactive substances. Today’s prospector benefits by the Canadian National Research Council’s development of a Geiger counter that weighs but a pound and is small enough to be lowered into a drill hole.

He benefits, too, by the United Slates Atomic Energy Commission’s publication of a handbook, Prospecting for Uranium (available from the U.S. Government Printing Office for thirty cents), which tells in hardheaded language what to look for and where to look for it, and how to dispose of it once it is found. The Commission guarantees for the next ten years to pay a minimum price of $3.50 per pound of contained U3O8 for small lots of domestic refined uranium, and $3.50 per pound of the recoverable oxide, less refining costs, for small lots of ore or mechanical concentrates assaying at least 10 percent U3O8.

There is also a bonus of $10,000 for the discovery of a new deposit and the production from it of the first twenty tons of uranium ore or mechanically produced concentrates assaying 20 per cent or more of uranium oxide. Comparable guarantees apply for uranium-bearing carnotite or roscoelite ores of the Colorado plateau area.

The sourdoughs strike gold

Samples of ore come piling into the Atomic Energy Commission’s raw materials laboratory in New York from all parts of the country at the rate of a dozen or more a day. Significant or not in their content of the precious metal, they evidence action. Marty Hess, Colorado prospector, reports a pitchblende discovery by another prospector in southern Nevada. Next, Marty Hess is directing meetings of the Nevada state uranium school at Reno, under sponsorship of the state department of vocational education.

Gilbert LaBine, who made the famous Canadian radium strike in the thirties, lectures at the Prospectors Institute in Los Angeles, warning prospectors not just to skim over promising territory. Mrs. Maggie Baker of Williams, Arizona, makes a uranium ore strike in the northern part of her state, the ore being classified as carnotite and termed among the richest uncovered in the nation. An operator of conducted tours in Utah warns tourists that uranium-bearing rocks collected as souvenirs will fog camera film in their suitcases.

Singapore reports prospecting to start in Malaya following an announcement that the United Kingdom will purchase uranium and thorium ores containing more than 10 per cent of radioactive materials. Paris broadcasts to Madagascar, Reunion, and the Somali Coast that the new strata of uranium discovered at St. Sylvestre will put Prance in a position to supply its own needs for the construction of a second atomic pile.

Rio de Janeiro declares that the monuzite sands of the State of Espirito Santo are not being secretly exported, and that two companies are making studies of them. A new strike of uranium at Lone Pine in the Hartz Range, Australia, is regarded as emphasizing Australian prospecting activ ity.

The Government of India enters a fifteen-year agreement with two French concerns for the processing of southern India’s monazite sands, which sometimes have traces of uranium. Extensive deposits of uranium are announced by a Mexican geologist as having been discovered in the State of Oaxaca. Donald B. MacMillan on his twenty-eighth scientific expedition to the Arctic will explore for uranium as well as other things.

The Argentine press announces discovery of important deposits on the slopes of the Andes mountains. A canyon east of Penticton, British Columbia, the eastern slope of the Rockies in Colorado, and five areas northwest of Sault Ste. Marie, Ontario, are other sites where st takes are reported. Discovery of a seam of uranium ore in Devon, England, is made known, with comment that the seam will not be worked while high-grade pitchblende can be bought more cheaply from the Belgian Congo, but that it will be used as a training area for prospectors.

Many of these reports, of course, will be found to fall into the traditional class of “thar’s gold in them thar hills.” Yet compared with the Atomic Energy Commission and its hard-working staff harassed by time-wasting abortive probes, or with the statesmen of the world balked at a solution of the problem of the atomic bomb, or with the average citizen perplexed and worried by these phenomena, today’s sourdough may have the best of the atomic age, as be puts his Geiger counter carefully out of reach of the fire as instructed, and relaxes in camp at sundown to figure out which hill he’ll cross tomorrow to have a look at the other side.