314 DESCRIPTIONS OF MINERALS. 



For other analyses of hydromica slates, see Dr. Genth's report on 

 the Mineralogy of Pennsvlvania ; also Geological Report of F. Prime, 

 Jr., for 1874, p. 12. 



Parophite. The material of a schist or slate — Parophite Schist — 

 ■which cuts like massive talc, is of greenish, yellowish, reddish, and 

 grayish colors, and is probably a daiuourite or hydromica slate, with 

 some free silica (quartz). An analysis afforded Silica 48*46, alumina 

 27"55, iron protoxide 5 "08, magnesia 2'02, lime 2 "05. ooua 2- '35, potash 

 516, water 7 14=99 81. It is from Pownah Vt., and St. Nicholas, 

 Stanstead, and other neighboring parts of Canada. 



Seriate. A damourite-like mineral, with the pearly lustre of talc, 

 and the composition of a hydrous mica ; it is the basis of a glossy 

 schist ; near Wiesbaden. The scales are described by Eosenbusch as 

 appearing fibrous when highly magnified. Analysis afforded Silica 

 49"00, alumina 23*65, iron protoxide" 8 "07, magnesia 094, lime 0'63, 

 soda 1-75, potash 9 '11. water 3"47, titanic dioxide 1'39, silicon fluoride 

 1 -60=100-14. 



Paragonite. A hydrous mica containing soda in place of potash. 

 From Mount Campione, in the region of St. Gothard. Color whitish, 

 grayish, yellowish, greenish. Analysis afforded Silica 46 '81, alu- 

 mina 4006, magnesia 0*65, lime 1*26, soda 6 40, potash trace, water 

 4'82=100. Pregrattite. from the Tyrol, afforded soda 7 '06, potash 

 1*71, water 5 '04 ; it exfoliates like the Vermiculites. Cossaite is here 

 included. 



Gfroppite. A rose-red to brownish-red foliated mineral from Gropp- 

 torp, Sweden. 



EuphyUite. Mica -like, with folia rather brittle, pearly lustre, 

 white or colorless. Contains much sodium. An analysis afforded 

 Silica 41*6, alumina 423. lime l'o, potash 3'2, soda 5'9, water o '5 = 100. 

 Occurs with corundum at Union ville, Delaware County, Pa. 



IhJUacherite. Mica-like ; strong pearly in lustre, grayish white to 

 white ; elastic. Analysis obtained 7 '61 potash, 1*42 soda, 4'65 baryta, 

 and 4*43 water, besides silica, alumina, etc. 



Gookeite. In minute mica-like scales, and in slender six-sided 

 prisms. Affords only 2 - 57 of potash, with 2 '82 of lithia ; the water 

 13 "41 per cent. Occurs on crystals of red tourmaline at Hebron and 

 Paris, Me,, and has proceeded from its alteration. Xamed after Prof. 

 J. P. Cooke, of Cambridge, Mass. 



Yoigtite is the mica of a granite at Ehrenberg, near Ilmenau, which 

 has the composition of biotite. plus 9 to 10 per cent, of water. 



Ro8coelite. A vanadium-mica, of dark brownish-green color, occur- 

 ring in micaceous scales, and affording over 20 per cent, of vanadium 

 oxides, along with 47'69 of silica, 14*10 of alumina, 7 "59 of potash, 

 496 of water, and a little magnesia and soda. From Granite Creek 

 Gold Mine, El Dorado County7 California. 



Fablunite, 



In six and twelve-sided prisms,, usually foliated, parallel 

 to the base, but owing its prismatic forms to the mineral 

 from which it was derived. Folia soft and brittle, of a 



