RECENT ACCESSIONS IN TliE DIVISION OF APPLIED 

 GEOLOGY. 



By Earl V. Shannon, 



Assistant Curator of Geology, United States National Museum. 



Owing to curtailment of imports and the urgent demand for certain 

 unusual mineral products for use in war industries, the recent World 

 War acted as a great stimulant to the mining industry, particularly 

 in connection with what are popularly known as the minor minerals 

 and rare earths. In endeavoring to do its part in the work of aiding 

 production of these highly necessary raw materials, especial effort 

 was made by this department to build up its series, both exhibition 

 and study, of these ores and minerals with which the public was 

 naturally little acquainted. That this effort was successful is shown 

 by the large number of mining men who have visited the museum, 

 both during and since the war, to acquaint themselves with the 

 physical characteristics and associations of manj^ of these uncommon 

 ores. Some of the more important and striking of the materials 

 acquired in this work are described in the following brief summary of 

 the recent growth of the collections of applied geology. 



The most notable recent accessions and those of greatest general 

 interest are the ores of the rarer metals, most particularly the so-called 

 minor metals used in steel manufacturing, which include tungsten, 

 molybdenum, vanadium, and, to a less extent, chromium and titanium. 

 These are of the utmost importance in the manufacture of alloy and 

 tool steels which are used in the metal-working industries and are 

 essential in the manufacture of munitions. The growth of the exhi- 

 bition series of ores of these metals is in large measure due to the 

 personal efforts of Mr. Frank L. Hess, honorary custodian of the 

 collection of rare earths and rare metals. Through his extensive 

 acquaintance with producers both in this country and abroad, 

 Mr. Hess has been able to secure large numbers of exceptionally fine 

 examples, especially of tungsten and molybdenum ores. These are 

 too numerous to be described individually, and only a few of the larger 

 and more striking will be mentioned. 



Scheelite, or calcium tungstate, is one of the more important ores 

 of tungsten, and contains, when pure, 80.6 per cent of tungsten 

 trioxide. A specimen recently placed upon exhibition is presumably 

 the largest single mass of this mineral ever mined. This specimen, 

 which is 4 feet 8 inches in length and weighs in excess of 2,600 pounds, 



Proceedings U. S. National Museum, Vol. 58— No. 2339. 



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