288 PHYSIOGRAPHY. 



Yenite Yttro-Cerite. 



into an opake glass, which is likewise magnetic. Glass of borax is col- 

 ored by it, yellowish green. It is soluble in muriatic acid. 



2. Analysis. 

 By STROMEYER. 



Silica 29-278 



Protoxide of iron 52-542 



Lime 13777 



Protoxide of manganese ..... 1-587 



Alumina 0-614 



"Water 1-268 



3. It is found in beds in primitive rocks, with Pyroxene, Hornblende, 

 Garnet, Quartz and Magnetic Iron. 



4. Its principal locality is the island of Elba, where it is found in crys- 

 tals of considerable size. Other places where it is found, are Kapfer- 

 berg in Silesia, Norway, and Siberia. But a single locality is known 

 in the United States, which is at Cumberland, (R. I.) where it ex- 

 ists in long slender crystals traversing Quartz in seams and associated 

 with Magnetic Iron and Hornblende. 



YTTRO-CERITE. Prismatic Fluor-Haloide. 



Primary form. Oblique rhombic prism ? 



Massive : composition granular. Cleavage parallel with 

 the sides of an oblique rhombic prism, whose lateral planes 

 incline under angles of about 108 30'. Fracture uneven. 

 Lustre vitreous to pearly. 



Color vitriol-blue, inclining to grey and white ; some- 

 times white on the surface. Opake. 



Hardness =4*5. Sp. gr. =3-447. 



1. Before the blow-pipe, it loses its color and becomes white before 

 it glows, but is infusible by itself. With sulphate of lime, it melts into a 

 globule, which becomes white on cooling. 

 2. Analysis. 

 By BERZELIUS. 



Lime 47-63 



Fluoric acid 25-05 



Yttria 911 



Oxide of cerium 18.22 



