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This discovery was followed by Madame Curie's demonstration of the fact that certain specimens of pitchblende, a mineral which contains compounds of uranium and of many other metals, are extremely radio-active, and by the separation from pitchblende, by Monsieur and Madame Curie, of new substances much more radio-active than compounds of uranium or of thorium.
The light is pale blue. Down in the deepest pitchblende mines, where particles of radium have been hidden away since the creation of the world, they are still found shining with their strange blue light. The radium electrons pass through the space which separates every molecule in a solid body from another. The scientific theory is that no two molecules in any body, however dense, actually touch.
Roger and Tom stood quietly, listening, and when Roger heard the news he turned to Tom with a questioning look on his face. Tom merely nodded grimly. "But what are you doing here with this load of pitchblende?" Quent persisted. "Everything would have been all right, even with the screens letting go," explained Ross, "if it hadn't been for Corbett and that big jerk Astro.
But some isotopes of uranium and thorium have little beta, with some alpha and gamma, so Baxter concluded we had powdered uranium ore. There are many kinds of ore. Pitchblende is the best, but carnotite, which is a gray rock with yellowish streaks, is also good ore. Got it now?" Jan Miller asked, "How do you know all this, Rick?" The boy chuckled.
To that which accompanied barium taken from the same ore they called Radium and to the substance which was found among the rare earths of the pitchblende Debierne gave the name Actinium. None of these elements have been isolated, that is to say, separated in a pure state from the accompanying ore.
Radium does not seemingly manifest itself when distributed through pitchblende; and there are doubtless other such substances in which it can be imprisoned. Possibly these may belong to that class of "inert" elements discovered or isolated by Sir William Ramsay.
But this radioactivity hardly attains the ten-thousandth part of that presented by uranium, or the ten-millionth of that appertaining to radium. Two other bodies, polonium and actinium, the one characterised by the special nature of the radiations it emits and the other by a particular spectrum, seem likewise to exist in pitchblende.
The insoluble barium and radium sulphates, after being converted into chlorides or bromides, are separated by repeated fractional crystallization. One kilogram of impure radium bromide is obtained from a ton of pitchblende residue after processes continued for about three months during which time, five tons of chemicals and fifty tons of rinsing water are used.
Curious as to the reason why Pax had isolated himself in this frozen wilderness, they next examined the high cliffs which shut in the valley on the west and against the almost perpendicular walls of which he had played the Lavender Ray. These cliffs proved, as Bennie had already suspected, to be a gigantic outcrop of pitchblende or black oxide of uranium.
He wasn't after force in pin-point quantities: he wanted bulk results. Yet I believe that, after all, what he sought was a sort of higher power of radium. The phenomena were related. And he had some of that concentrated essence of pitchblende in the chest when we started. Oh, not much: say about twenty thousand dollars' worth. Maybe thirty. For use? No; rather for comparison, I judge.
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