LIST OF PUBLICATIONS. 



171 



Hess, Frank L. Tungsten minerals 



and deposits. 



Bull. U. S. Geol. Surv., 

 No. 652, 1917, pp. 

 1-85, pis. 1-25, 

 figs. 1—4. 

 An attempt is made to gather 

 into this bulletin the kno^n 

 general facts about tungsten, 

 the minerals in which it is 

 found, the kinds of deposits 

 from which these minerals have 

 been obtained, and other in- 

 formation which will answer as 

 many as possible of the ques- 

 tions asked the Survey, and to 

 show by illustrations, colored 

 and uncolored, the appearance 

 of typical specimens of the 

 various tungsten minerals. The 

 purpose has been to make this 

 paper of interest and use to the 

 prospector and miner, and also 

 to those who have no particular 

 knowledge of minerals. Much 

 of the material on which this 

 report is based, including a 

 number of the illustrated speci- 

 mens, is the property of the 

 Museum. 



Koch, Loris H. Green ealcite from 

 Glens Falls, N. Y. 



Amer. Mineralogist, 2, 



No. 10, Oct., 1917, 



p. 121. 



The author determined by 



analysis that the unusual green 



color of a specimen of ealcite 



in the Museum's collection was 



probably due to a minute 



amount of chromium present iu 



its composition. 



A new occurrence of ptilolite. 



Amer, Mineralogist, 2, 

 No. 12, Dec, 1917, 

 pp. 143, 144. 

 Records the occurrence at 

 Challis, Idaho, of the rare 

 species ptilolite, a hydrated sili- 

 cate of alumina, lime, and the 

 alkalies, hitherto known only 

 in minute amount from three 

 places in Colorado. 



Larsen, Esper S. The probable iden- 

 tity of uranotballite and liebigite. 



Amer. Mineralogist, 2, 



No. 7, July, 1917, 



p. 87. 



The author determines by an 



optical study that these two 



minerals are probably identical, 



and recommends that the name 



Labsen, Esper S. — Continued. 



uranothallitc be retained since 

 the first accurate description 

 was published under that name, 

 although liebigite has priority. 

 Based partly on Museum ma- 

 terial. 



Merrill, George P. A second meteorite 

 find in Florida. 



Amer. Journ. Soi., 44, 



Jan., 1918, pp. 64, 



65. 



Brief description without 



chemical analysis of a fragment 



found, but time of fall unknown. 



Of chief interest as being the 



second find of meteoric stones in 



Florida. 



A peculiar fibrous form of opal. 



Amer. Mineralogist, 3, 

 No. 2, Feb., 1918, 

 pp. 11, 12. 

 Describes a peculiar fibrous, 

 almost asbestiform, opalescent 

 siliceous replacement of the or- 

 ganic .matter of wood. 



Tests for fluorine and tin in 



meteorites with notes on maskelynite 

 and the effect of dry heat on me- 

 teoric stones. 



Proc. Nat. Acad. 8ci. t 

 4, No. 6, June, 

 1918, pp. 176-180, 

 figs. 1-5. 

 Gives the results of tests 

 which seemingly show that 

 neither fluorine nor tin are con- 

 stituents of meteoric stones ; 

 that the so-called maskelynite is 

 a feldspathic glass, and that the 

 black color of some chondritic 

 stones may be due to heating as 

 contended by Meunier. 



Watson, Thomas L., and R. E. Beard. 

 The color of amethyst, rose, and 

 blue varieties of quartz. 



Proc. U. 8. Nat. Mus., 

 5.1, No. 2220. Aug. 

 11, 1917, pp. 553- 

 563. 

 Gives the results of experi- 

 ments by the authors on the 

 color of several varieties of 

 quartz, and a brief summary 

 and discussion of the work of 

 others on the same mineral. 

 Concludes that the amethystine 

 colors are due to manganese ox- 

 ide probably in colloidal par- 

 ticles of submicroscopic size ; 

 that the color of rose quartz can 



