MINERAL^from GREENLAND. 385 



acids : Ammonia throws it down in gelatinous flocks : Zinc 

 does not precipitate it at all. 



h. The white oxide of cerium, mentioned by Hisinger and 

 Berzelius, and defcribed by Vauojjelin, did not prefent itfelf 

 to me in any of my experiments ; unlefs the white flocks preci- 

 pitated by ammonia from the original folution be confidered as 

 white oxide. They became brown on drying, and when heat- 

 ed to rednefs, were certainly converted into red oxide. 



As cerium, as well as iron, is precipitated by fuccinate of 

 ammonia, the preceding method of feparating the two from 

 each other was not unexceptionable. Accordingly, in fome 

 fubfequent; analyfes, I feparated the cerium by means of oxalate 

 of ammonia, before I precipitated the iron. I found that the 

 proportions obtained by the analyfis above defcribed, were fb 

 near accuracy that no material alteration is neceflary. 



8. The liquid, thus freed from iron, alumina, and cerium, 

 was mixed with carbonate of foda. It precipitated a quantity 

 of carbonate of lime, which amounted, as before, to about 17 

 grains, indicating 9.2 grains of lime. 



From the preceding analyfis, which was repeated no lefs 

 than three times, a different method being employed in each, 

 the conftituents of allanite are as follows : 



Silica, - - - 35.4 



Lime, - - 9.2 



Alumina, - - 4.1 



Oxide of iron, <- - 25.4 



Oxide of cerium, - - 33.9 



Volatile matter, - 4. 



112.0 



Vol. VI. P. II. 3C 



