Minerals and Gems Ji 



The research laboratory is now equipped with a Gold- 

 schmidt Two-circle Goniometer for measuring crystal angles, 

 and the initial work with this instrument has 

 Research and a i re ady demonstrated that there is a considerable 

 amount of material in the Bement Collection 

 which, subjected to crystallographic study, will yield new 

 forms. 



Work on the list of new crystal forms of minerals has been 

 completed. In addition, the Curator has published during the 

 year "A Model for Demonstrating Crystal Structure," Ameri- 

 can Journal of Science, XLIX, pages 259-264, and "The Per- 

 centage of Accuracy in Cutting Semi-Precious Stones," The 

 Jewelers' Circular, February 4, 1920. 



The year has been a notable one with regard to the number 

 and value of the specimens which have been added to the col- 

 lections through gifts. From a point of view of 



ccessions scientific interest, by far the most important of 

 these gifts consists of a suite of 68 mounts, received through 

 Dr. George F. Kunz from Professor Alfred Lacroix, of the 

 Museum d'Histoire Naturelle, Paris. These are practically all 

 type specimens of the material described by Professor Lacroix 

 in his monumental work on the Mineralogy of France and Her 

 Colonies, and they include 18 species and varieties hitherto 

 unrepresented in our collections. The Department has also 

 acquired, through the gifts of Mr. Harry F. Guggenheim and 

 Mr. H. C. Bellinger, excellent series of Chilean and Bolivian 

 minerals, including tin and tungsten ore minerals from Cara- 

 coles, Bolivia, and Rancagua, Chile; also a beautiful and 

 highly interesting series of 25 specimens of the sulphate min- 

 erals of Chuquicamata, Chile. Many of these latter are beau- 

 tifully crystallized. Dr. Henry Buttgenbach, of Brussels, has 

 presented a specimen of the new lead-manganese oxide Cesaro- 

 lite from Tunis, which was discovered by him and named after 

 Professor G. Cesaro, of Liege, Belgium. Mr. C. J. Osman 

 has donated a finely crystallized specimen of the rare mineral 

 Inoyite from Hillsborough, New Brunswick, a new locality 

 for this species, which was hitherto unrepresented in the col- 

 lections. The New York Mineralogical Club has presented a 



