112 REPORT OF NATIONAL MUSEUM, 1930. 



rough as contrasted with the cut stones, and artificial and imitation 

 stones. In an upright case between the windows at the center of 

 the hall are many semi-precious stones such as are utilized in the 

 manufacture of small ornaments rather than as objects for personal 

 adornment. It may be added that in building up the collection, an 

 attempt has been made to show the possibilities of common-place 

 material; that there are a goodly number of stones, in themselves 

 of little intrinsic value, which, when properly cut and mounted, are 

 not merely beautiful but have the additional value of being out of 

 the line of the usual material sold in the shops. In this connection, 

 particular attention may be called to the cabochons of silicified 

 wood, obsidian, epidotic granite, and the green feldspar, amazon- 

 stone. 



Researches. — As may readily be inferred from what has gone 

 before, but a limited portion of the time of the scientific force can 

 be devoted to research. The head curator has continued his work 

 on meteorites, as in previous years, under a grant from the National 

 Academy of Sciences. With the able assistance of Miss Moodey^ he 

 has also prepared and submitted for publication a handbook and 

 catalogue of the gem collection, which, it is expected, will be issued 

 during the coming year. 



Mr. Earl V. Shannon, assistant curator in the division of economic 

 geology, has carried on a number of investigations, a portion of 

 which have an economic bearing. A voluminous manuscript on the 

 minerals of Idaho, based in large part on Museum material, is 

 practically finished, and a crystallographic study of the datolites of 

 Westfield, Massachusetts, is well along toward completion. Materials 

 collected in Connecticut during the autumn have been investigated 

 and made the subject of two papers, one on triplite from Chatham 

 and the other a lengthy study of the minerals of Long Hill, in 

 Trumbull. Shorter investigations on minerals of the chlorite group 

 include analyses and the optical examination of amesite and corundo- 

 phylite from Chester, Massachusetts ; of chromium bearing chlorites 

 from California and Wyoming; and of stilpnomelane from New 

 Jersey. A new mineral, bismutoplagionite, has been described. 

 Mineralogical examinations in the reserve series of ores have re- 

 sulted in the preparation of papers on boulangerite and bindheimite, 

 both of which were shown to be more common ore minerals than 

 heretofore supposed. 



Assistant Curator Foshag of the mineral department has investi- 

 gated a considerable number of minerals and submitted for publica- 

 tion papers on sulphohalite, glaserite, hydrotalcite, and the hydro- 

 talcite group of minerals, thaumasite. spurrite. and hematite. Some 

 exceptional specimens received in the department have been made 



