HOFFMAN ON THE MINERALOGY OF NEVADA. 735 



Diallogite. Occasionally fouud at Morey, where it accompanies calcite 

 and rbodocrosite ; rarely at Reese River. 



Dolomite. Is found in various portions of the limestone formations, 

 although sometimes rarely in crystals. The variety known as pearl 

 spar occurs in moderately sized crystals twenty miles south of Eureka. 

 A ferriferous variety, usually known as brown spar, occurs in the 

 eastern portion of the State (exact locality unknown). This was sup- 

 posed to contain a large percentage of chloride of silver, the finders 

 arriving at this conclusion by its grayish-brown color alone. Crystals 

 occur of from two to three inches in length. An examination of one 

 of the samples resulted as follows : — 



G. = 2.92. 



Carbonate of lime 55. 38 



Carbonate of magnesia 39. 90 



Carbonate of iron 3. 03 



Carbonate of manganese 1.64 



99,95 



Another variety found in the same region is undoubtedly aiikeriie 



{q. v.). 

 Emholite. In small quantities at Bull Run, Cope, and Eureka Districts ; 



more abundant at Mineral Hill, San Antonio, Belmont, Montezuma, 



Palmetto, and Hyko. 

 Epidote. Locality unknown. 

 Feldspar. See Orthoclase. 

 Flint. See i^'ilica. 

 Fluorite. In small green crystals in the White Mountains, near the 



dividing line between Nevada and California, west of Columbus. 

 Frieslebenite. Belmont. (Loew.) 

 Oalenite. In large quantities and frequently of large cubic forms in 



Galena District; in cubes and dodecahedra at Reese River; a crystal 



of the latter variety measured over two inches in diameter. Massive 



and associated in moderate quantities with silver-ores in nearly all 



the districts to a greater or less extent. 

 The following varieties are found in more decided quantities in the 



following-named districts: — 



a. Argentiferous : rarely at Belmont and Hyko ; sparingly at Bull 

 Run, Mineral Hill, and Silver Peak ; abundant at Battle Mountain 

 and Galena Districts. An exceedingly rich variety occurs sparingly 

 four miles west of Gold Mountain. 



b. Auriferous: sparingly but very rich at Silver Peak. 



Oarnet. Good crystals, but very small, from the Black Caiion, Colorado 

 River. Impure, fractured crystals, nearly one and a half inches in 

 diameter, occur. 



Gay-Lussite. Sparingly in the dry soil of Fish Spring Valley. 



