1940: Mineralogy

Mineralogists the world over continued to make important contributions to the science during 1940. To be sure, the flow of publications from abroad lessened considerably during the year, but much of this may be due to interrupted transportation services. Also, but little effect of the war can be observed in the character of the research reported upon in the scientific journals. The range of subjects of the articles published is the same as in times of peace. No doubt many mineralogists in the war-torn countries are engaged in researches which may be of benefit to the military arm, but reports of such activities are not being published at this time.

At least one book on strategic mineral supplies has appeared in the United States. This book discusses the reserves, production, consumption, uses and substitutes of such minerals as mica and the ores of manganese, nickel, chromium, tungsten, tin, aluminum, antimony, mercury, platinum, iodine, and nitrogen, materials in which the United States would be insufficiently supplied during time of war. Outstanding among deficiencies in strategic minerals in the United States is tin, for only one-tenth of one per cent of the tin consumption of this country is supplied through domestic production.

Several monographs were published during 1940 (or late in 1939) in the field of mineralogy. One such was a volume on the minerals of Peru, in which 1,617 minerals in the Natural History Museum at Lima are described and their localities listed. Of petrologic interest is a monograph on the anorthosites of the Minnesota coast of Lake Superior. These anorthosite bodies range in size from single crystals of plagioclase feldspar to masses over a quarter of a mile across.

Several new falls of meteorites were recorded during the year. Natural glass tectites, which may or may not be of meteoritic origin, continued to interest many investigators. The total number of papers on meteorites listed in a British abstract journal was 43, which is about half the number listed in each of the two preceding years. However, this does not necessarily denote lessened interest in these extra-terrestial visitors, as the receipt of foreign publications by the editors of the British journal has no doubt fallen off.

Growing interest has been observed in the last few years in the clay minerals. Through the application of X-ray techniques, the individual minerals making up a clay can be identified, and many papers during the year contained mineralogical descriptions of various clays. A surprising discovery recorded during the year was the finding of ceramic clay in Hawaii. A geologist would naturally classify an area of volcanic islands as a most unlikely place to find commercial clay, but on several of the islands in the Hawaiian group a thin layer of white, high quality clay was discovered beneath the vegetation in bog areas. A combination of poor soil drainage, high soil acidity, and reducing conditions resulting from the peculiar plant growth in such areas probably led to the development of a relatively iron-free clay from rocks originally high in iron and low in silica. These clays are of great scientific interest, but their economic value is questionable, as the thickness of the different deposits is only a few inches, and they invariably occur beneath a dense overburden of plant material and at long distances from any road.

Several reports were made on the mineralogical changes which take place during metamorphism. Contact metamorphic effects around the Katahdin granite in Maine, and at Rye Patch, Nevada, were described. A monograph on the igneous rocks and metamorphism of the Adirondack region appeared during the year.

A revival of interest in pegmatites was apparent during 1940 with the publication of at least six papers on these interesting mineral deposits in the United States alone. The localities include the beryllium-rich deposits of Mount Antero, Colorado, the lithium pegmatites of the Keystone district in South Dakota, corundum-bearing pegmatites at Glen Riddle, Pennsylvania, the tantalum-containing deposits of the Bridger Mountains, Wyoming, and still other types of pegmatites in New York and Maine.

Many papers were published during the year on X-rays and crystal structure, showing an increased interest in that branch of mineralogy. Continued investigation was also made in techniques, and an improved electromagnetic separator for mineral grains was described.

No better criterion exists of the research activity of mineralogists than the number of new mineral species discovered each year. Because of the wide geographic distribution of publication mediums, it is customary to make this count from the list published during the current year in the American Mineralogist, the journal of the Mineralogical Society of America. The actual discovery date may of course fall in an earlier year. During 1940 the number of new minerals listed in this journal was twenty-seven, which compares very favorably with the eighteen listed during 1939 and the fifteen during 1938. Likewise during the year appeared the fifteenth list of new mineral names, published by the former Keeper of minerals in the British Museum. This list covers the new names introduced during 1938, 1939, and the first half of 1940. It contains 225 names, of which 117 are recognized by the author as new minerals or as definite varieties of already existing minerals. See also CHEMISTRY; GEOLOGY.