Reg! eS Ae rank “ge pee Oe 
1894.] Mineralogy and Petrography. 519 
ated. The same author” has analyzed ettringite from the Lucky Cuss 
Mine, Tombstone, Arizona. The mineral is in aggegrates of radiating 
fibres resembling in appearance a fibrous pectolite. These fibres are 
doubly refracting and have apparently a parallel extinction. The 
analysis of selected material gave: 
SiO, AlĻO, CaO SO, H,O at 115° Loss at red heat Total 
1.901 10.157 25.615 17.675 33.109 10.872 = 99.329 
Reduced, these figures. correspond with the formula 
2 [((Hut Ca Al,) O,], SO,+8 H,O. 
` Pentlandite occurs at the Sudbury Mine in Ontario, intergrown with 
massive pyrrhotite. Penfield finds" its density to be about 5, and its 
composition: S =83.42; Fe = 30.25; Ni = 34.23; Co = .85; gan-. 
gue =-.67. This corresponds to (Fe Ni) S, in which Fe: Ni = 1:1.32, 
The three supposed new sulphides folgerite, blueite and whartonite 
described by Emmens from this locality are thought by Penfield to be 
nickeliférous pyrite (blueite and whartonite) or mixtures of pentlan- 
dite with some impurity (folgerite). ee 
Hidden reports" two new localities for gem turquoise. One is in the 
Cow Springs district of Grant Co., N. M., fifteen miles south of the 
Azure Mining Company’s claim in the Burro Mountains, and the 
other is 150 miles east of the Burros in the J arilla Mountains, Doña 
Ana Co., in the same State. Both localities were formerly worked by 
the natives. The matrix of the mineral in both cases is a trachyte 
traversed by fissures filled with quartz, limonite, kaolin, jarosite and 
other minerals. The kaolin is the result of alteration of the trachyte 
and the turquoise is regarded as a further alteration product of the 
kaolin. 
A list of the minerals known 
bard.” Among these isa tale which 
occurs in fibres like those of asbestus, with an index of refraction = 
15-16, an optical angle 2V = 60°, and a density of 2.74-2.88 
Their composition as found by Packard is: 
to occur in Michigan is given by Hub- 
the author calls beaconite. It 
“CF, also Zeits. f. Kryst., XXII, p. 16. 
"Ib., XLV, 1893, p. 493. 
181b., XLVI, 1893, p. 400. à 
= Rep. State (Mich.) Board of Geol. Survey, Lansing, 1893, p. 17 1. 
