POSITION OF THE UNITED STATES
As outlined above, it can be readily seen that the United States is dependent upon Brazil and India for its raw materials, as domestic deposits are not large enough to furnish the required supply and cannot be worked in competition with the more cheaply mined foreign deposits.
The average concentrate obtained in the Carolinas runs about 3¹⁄₂ to 4 per cent. thorium oxide; that obtained in Brazil averages somewhat over 8 per cent. Under such conditions it is difficult for the Carolina monazite to compete with that from Brazil or from India. In addition, a very considerable amount of the Carolina monazite available has been removed. The old workings are more or less covered up and the whole industry has become completely disorganized.
Whilst these deposits were being mined and operated farmers were in the habit of making their own concentrate in crude sluice boxes. The product thus obtained averaged about 35 per cent. monazite. The concentrates were then sold to a refinery, where it was best treated by electromagnetic separators, such as the Wetherill machine. The final product obtained from these machines was ready for chemical treatment for the extraction of the thorium.
Practically the same treatment is given to the monazite from Brazil and India. As the concentrate obtained is of much higher grade, the additional charges for freight and duty, which are not borne by the Carolinas product, are more than offset. Undoubtedly, unless a very high tariff is placed on the monazite from Brazil and India, our future supplies will come from these two sources, at least for some time. It is very doubtful whether with a high tariff the Carolina deposits could furnish the monazite required in this country, even for a few years, and under the most favorable conditions it would take some time, possibly six months to a year, to revive the industry.
The Allies and practically the whole world are dependent upon the United States for the manufactured products, thorium nitrate and gas mantles. Whether this monoply will continue is doubtful, as there is a movement in England to encourage both the thorium nitrate and the gas-mantle industry.