CERIUM. 441 



LOCALITY. 



This mineral, still rare, has been foilnd since the commencement of the Survey, in a vein 

 in feldspar and quartz, in the town of Monroe, Orange county. I received a specimen from 

 Dr. Horton, which has the following characters : The mineral is massive, although it has 

 the appearance of being a part of a crystal. Colour brownish-black. Dull on the outside, 

 but the fresh fracture has a resinous or imperfectly metallic lustre. Powder brown. Opaque 

 or feebly translucent on thin edges. Very brittle. Fracture uneven or small conchoidal. 

 Hardness about 6.0. Specific gravity 3.60 to 3.65. It forms a jelly with muriatic acid. 



An analysis of this mineral gave the following results, viz : 



Protoxide of cerium, 24. 90 



Silica, 30.50 



Alumina, 11. 25 



Protoxide of iron, 22. 27 



Lime, 9.87 



This approaches very nearly to the composition of the Cerine found at Bastnaes, near 

 Riddarhytta, in Sweden.* The Cerite of Hisinger, Thomson and PhiUips, Cererite of Beu- 

 dant, appears to be quite a distinct mineral. 



* The composition of this mineral, according to Hisinger, is as follows : 



Silica 30.17 



Alumina, 11.31 



Piotoiide of cerium, 28.19 



Oxide of iron, , 20.72 



Lime, 9.12 



Oxide of copper, . . 0.89 



Volatile matter 0.40 



MiN. — PartFI. 56 



