902 DESCRIPTIONS OF MINERALS. 
purple fluor- spar; sometimes reddish-brown. Opaque. 
Lustre glistening. H.=4-5. G.=3:4—-3°5. 3 
Composition. Fluorine 25:1, lime 47:6, cerium protox- 
ide 18:2, and yttria 9:1. Infusible alone before the blow- 
pipe. 
Obs. From Finbo and Broddbo, near Fahlun, in Sweden, 
with albite and topaz in quartz. Also from Mt. Mica, 
Maine ; Massachusetts, probably in Worcester County; and 
from Amity, Orange County, N.Y. 
Fluocerite and Fluocerine are other fluorides containing cerium, from 
Sweden. 

Samarskite. 
Trimetric. 2A 7=122° 46". Usually massive, without 
cleavage, with a velvet-black color and shining submetallic 
lustre. Streak dark-reddish brown. Opaque. H.=5°d-6. 
G.=5'6-5'8. i 
Composition. Analyses of the American afford columbic 
and tantalic pentoxide, with sesquioxides of yttrium (12-15 
per cent.), cerium, iron, and oxide of uranium. In the 
closed tube decrepitates and glows. B.B. fuses on the 
edges toa black glass. With salt of phosphorus in both 
flames, an emerald-green bead. 
Obs. Occurs at Miask, in the Ural; also in masses; 
sometimes weighing many pounds, at the Mica mines of 
Western North Carolina, along with columbite. 
Nohlite is near samarskite, but contains 4°62 of water. 
Fergusonite. A hydrous columbate of yttrium, erbium, cerium. 
Color brownish black ; lustre dull, but brilliantly vitreous on a sur- 
face of fracture. B.B. infusible, but loses its color. From Sweden, 
Cape Farewell, Greenland, and Rockport, Mass. 
Kochelite is near fergusonite. 
Yttro-tantalite. A tantalate and columbate of yttrium, erbium, and 
iron. The different varieties are the black, the yellow, and brown or 
dark-colored. They are infusible. From Ytterby, Sweden, and at 
Broddbo and Finbo, near Fahlun. : 
Huxenite. A columbate and tantalate of yttrium, uranium, erbium, 
and cerium. Massive. Color brownish black. Streak reddish brown. 
B.B. infusible. From Norway ; also from N. Carolina. 
Supylite. A columbate and tantalate of erbium and yttrium, re- 
sembling fergusonite in aspect. From Amherst County, Va. 
Pyrochlore, Microlite, Disanalyte, under CALCIUM, p. 214. 
LEschynite. Tn crystals, black to brownish yellow ; lustre resinous 
to submetallic ; streak gray to yellowish brown or black. H.=5-6. 
G.=4:°9-51. Acolumbate and titanate of cerium, thorium, and lan- 
thanum. From Miask, in the Urals, in feldspar with mica and zircon. 
Polymignite and Polycrase. Related to eschynite. 
