264 Klaproth o)i the Chemical Analyvs 



d. The remaining fluid was boiled with carbonate of potassa ; 

 it afforded 9 grains of carbonate of lime, equal to 5 grains of pure 

 lime. The fluid was then saturated with nitric acid, and tested by 

 prussiate of potassa, which gave slight traces of the presence of 

 copper. One hundred parts therefore of cererit contain. 

 Oxide of cerium . . Cc .... 54.50 



Silica — a . . . . 34.50 



Oxide of iron ... — b . . . . 3.50 



Lime — d . . . . 1.25 



Water A2 . . . . 5. 



98^75 



Properties of the Oxide of Cerium. 



a. Thrown down from its nitric solution by ammonia, oxide 

 of cerium appears in the form of a muddy-red precipitate, which 

 dries into a transparent and hard mass ; when ignited, it acquires 

 the form of a cinnamon-brown powder. 



b. Carbonated alcalis separate a white carbonate, of which 

 100 grains (precipitated by carbonate of ammonia) lost 23 grains 

 during solution in nitric acid; 100 grains of the same carbo- 

 nate lost by ignition 35 grains ; hence it is composed of 



Oxide of cerium 65. 



Carbonic acid 23. 



Water 12. 



100 



c. Before the blow-pipe, oxide of cerium becomes brilliantly 

 luminous, without fusion. With phosphate of soda it produces 

 a yellow bead which becomes colourless when cold. Borax 

 produces the same appearance. 



d. It undergoes no change by long-continued exposure to a 

 bright red heat in a charcoal crucible. 



e. Employed as an enamel, it gives a light-brown colour. 



f. Neither caustic nor carbonated alcalis dissolve the re- 

 cently precipitated oxide of cerium. 



f/. Carbonate of cerium is easily soluble in the acids, form- 

 ing a sweetish astringent neutral solution ; when diluted, the 



