202 Canfield, Hillehrand^ and Sohaller — Mosesite, 



Art. XX. — Mosesite, a Nexo Meyxnry Mineral from, Ter- 

 lingiia, Texas ; by F. A. Canfield, W. F. Hillebrand, and 

 W. T. Sohaller. 



Introduction, 



The name mosesite is proposed for a new mercury mineral 

 from Terlingua, Brewster Co., Texas, in honor of Prof. Alfred 

 J. Moses of Columbia University, New York, who first defi- 

 nitely described the interesting mercury minerals found in 

 Texas. The three minerals, montroydite, terlinguaite and 

 eglestonite, were named and definitely determined by him, and 

 he also gave a preliminary notice of a fourth new one (later 

 named kleinite). It is, therefore, with great pleasiire on on'r 

 part that we propose the name mosesite, which name, besides 

 perpetuating the high attainments of Professor Moses in the 

 science of mineralogy, is particularly appropriate as it links his 

 name with a group of minerals which he first definitely put on 

 record. 



General Description {F. A. Canfield). 



"While examining a recently acquired specimen of montroy- 

 dite and calcite the attention of the writer was attracted to 

 some small yellow crystals which were perched upon the crys- 

 tals of calcite. They did not join the montroydite but were 

 isolated and solitary' ; they appeared to lie upon the surface of 

 the calcite with but little or no bond. The slightest touch 

 would loosen them, leaving no scar upon the calcite but merely 

 a clean spot. A careful search revealed twenty-six crystals 

 which will weigh, perhaps, ten milligrams. Twenty-two of 

 the crystals are simple octahedrons, the others are spinel twins. 

 No other forms were observed and none of the mineral was 

 massive. 



Another specimen has lately been procured which is much 

 the finer in every way. Hundreds of crystals are scattered 

 over a surface (4™ x 6"^™) of calcite which rests upon the pink- 

 ish rock which is characteristic of the Terlingua specimens. 

 Nearly all of the crystals are spinel twins. They are fre- 

 quently grouped together in confused masses ; one polysynthe- 

 tic twin — a .5-ling — was seen. Simple octahedrons are rare. 

 None was modified by other forms. No other mercury mineral 

 is present on the specimen unless some delicate, elongated, 

 light yellow particles should prove to be kleinite. 



It is impossible to tell to what conditions these specimens 

 have been subjected. It is certain that the first specimen has 

 been badly treated, since it is bruised and very dusty. 



