J 1 6 M, Berzelius*s Analysis of some Minerals. [Aug. 



and that the phaenomena observed during rapid rotation are 

 such as we should expect fk>m those which 1 have so fully 

 described as aiising from rotation, without regard to its 

 velocity." \, W. B, 



iTohe continued.) 



Article VI. 



Analysis of some Minerals. By Mons. J. Berzelius.'*^ 



Phosphate of Yttria, 



This mineral was found by M. Tank, in the neighbourhood 

 of Lindenas, in Norway, in a gangue, chiefly consisting of 

 large grained granite, and accompanied by another mineral, 

 which, both by its external characters and those which it pre- 

 sents before tne blowpipe, perfectly resembles the orthite dis- 

 covered a year ago, at Skeppsholmen. 



The specimen of phosphate of yttria, sent to M. Berzelius, 

 was too small to admit of a perfect mineralogical description of 

 the mineral ; its form was irregular, with crystalline striae, like 

 those observed on imperfectly developed garnets. 



Its colour is brownish yellow, similar to that of the zircon, 

 from Fredrikswarns, with which, at first sight, it might easily be 

 confounded. Its specific gravity at 60°=4-5577 ; it is scratched 

 by steel. Its fracture is foliated in several directions ; its trans- 

 verse fracture is uneven, and splintery ; externally it is dull, but 

 the fohated fracture has a resinous lustre, and the transverse a 

 fatty one. In thin fragments it is serai-transparent and yel- 

 lowish. 



Before the blowpipe this mineral behaves much like phos- 

 phate of lime. Alone it does not fuse, but its colour becomes 

 deeper. Heated in a matrass, it gives off no water; with borax 

 it dissolves slowly, and forms a colourless glass, which becomes 

 milk-white by flaming, and, if saturated, whitens on cooling. 

 It dissolves with great difficulty in salt of phosphorus, and 

 forms a transparent colourless glass. This mineral differs from 

 phosphate of lime by the facility with which the latter dissolves 

 Dy the salt of phosphorus, forming, if the salt be saturated, a 

 glass which loses its transparency on cooling. The same, how- 

 ever, would happen with the phosphate of yttria, but the opera- 

 tion requires great time and labour. With carbonate of soda, 

 the assay produces a strong effervescence, and gives an infu- 

 sible, clear grey scoria. "With boracic acid it dissolves with 

 difficulty ; but if a morsel of iron be introduced into the glo- 



* Extracted from the Annales de Chimie. 



