On the ratio of the amounts of actinium and uranium in carnotites from Colorado

(Karl H. Fussler. The Actinium-Uranium Ratio in Colorado-Carnotite. Phys. Review, 9, No. 2, p. 142—1917).

It is accepted by investigators of radioactivity that actinium constitutes one of the products in the series of transformations of uranium. Indeed, actinium has not only always been found in uranium minerals, but Boltwood showed that the ratio of the amount of actinium to uranium from North Carolina uraninite varies within narrow limits, which speaks in favor of the above hypothesis. Fussler subjected carnotite from Colorado to investigation and showed that the amount of actinium in carnotite is proportional to the amount of uranium, while the ratio of the amount of actinium to uranium was found to be somewhat smaller than that of Boltwood.

I. Lazarev.