252 ANALYSES OF ROCKS AND MINERALS, 1880-1908. 
V. OXIDES AND HYDROXIDES. 
MANGANOSITE. 
From Franklin Furnace, New Jersey. Collected by ©. Palache. Analysis by G. 
Steiger. Sp. gr., 5.364. 
SiO, AlO3, and CaO absent. 
MONTROYDITE. 
From Terlingua, Texas. See Hillebrand and Schaller, Jour. Am. Chem. Soc., vol. 
29, p. 1189. Analysis by W. F. Hillebrand. 
SPINEL. 
Variety pleonaste. Separated from a pyroxenite found between South Meadow 
and Moore creeks, Madison County, Montana. Rock described by Merrill in Proc. 
U.S. Nat. Mus., vol. 17, p. 659. Sp. gr. of spinel, 3.89 at 32°.3. Analysis by L. G. 
Eakins. 
GAHNITE, 
A. From Gilmore’s mica mine, Montgomery County, Maryland, about 12 miles 
north of Washington, District of Columbia. Color, bottle green. Sp. gr., 4.59. An- 
alyzed by T. M. Chatard and described by him in Bull. 9. 
B. Dysluite from Sterling Hill, New Jersey. Collected by C. Palache. Analysis 
by W. T. Schaller. Sp. gr., 4.56. 
H20 at 105°... 
20 above 105° 
a Total Fe. bState of oxidation uncertain. ¢ Loss on ignition. 
