METALS. 



1. 2. 3. CERIUM, YTTRIUM, LANTHANUM. 



Cerium and Yttrium are not used in the arts. The spe- 

 cies are infusible alone before the blowpipe or only in the 

 thinnest splinters. 



YTTROCERITE. **? , 



Massive, of a violet-blue color, somewhat resembling a 

 purple fluor spar; sometimes reddish-brown. Opaque. 

 Luster glistening. H = 4 — 5. Gr = 3*4 — 3*5. 



Composition : fluoric acid 25*1, lime 47*6, oxyd of ceri- 

 um, 18"2, and yttria 9*1 . Infusible alone before the blow- 

 pipe. * 



. Obs. From Finbo and Broddbo, near Fahlun in Swe- 

 den, with albite and topaz in quartz. Also from Massachu- 

 setts, probably in Worcester county, and from Amity, Orange 

 county, N. Y. 



Flucerine and Basic Flucerine. These two fluorids of cerium have 

 a bright yellow or yellowish-red color. Infusible alone in the blowpipe 

 flame. They are from Sweden. 



Parisite. Occurs in bipyramidal dodecahedrons, (fig. 65, page 39,) 

 of a reddish-brown or brownish-yellow color and vitreous fracture. 

 Cleavage easy parallel to the base. Gr=4"35. Infusible alone. Com- 

 position : carbonic acid 23*5, protoxyds of cerium, lanthanum and 

 didymium 594, lime 3*2, fluorid of calcium 115, water 24. From 

 New Grenada. 



Lanthanite. Trimetric. In thin minute tables or scales of whitish 

 or yellowish color. H=25 — 3. Composition : carbonate of lantha- 

 num 77*48, water 24 09. From Bastnas, Swpden, and Saucon valley 

 n Lehigh Co., Pa. 



MOXAZITE. •, 



Monoclinic. In modified oblique rhombic prisms ; M 

 -^ M=93 10, e on a=140° 40, M : e=136 D 

 35 . Perfect and brilliant basal cleavage. Ob- 

 served only in small imbedded crystals. 



Color brown, brownish-red ; subtransparent 



to nearly opaque. Luster vitreous inclining 



to resinous. Brittle. H=5. Gr=4*8 — 5*1. 



Composition : oxyd of cerium 26'0, oxyd o 4 



ianthanum 23*4, thoria 17*95, phosphoric acid 28*5, with 



What is said of the blowpipe action of ores of cerium and yttrium 

 What is the appearance and composition of yttrocerite ] What i« 

 monazite ? 



