38 M. Hartwairs Examination of some Minerals. 



character of the rocks from which they rise, or which surround 

 them. By way of appendix, I will present, in the eighth and 

 ninth groups, the springs belonging to this class in Auvergne, 

 the Vivarais, and in the Pyrenees *. 



Examination of some Minerals. By M. Victor Hartwall f. 

 1. Fergusonite. 



This mineral, named in honour of Robert Ferguson, Esq. of 

 Raith, occurs near to Kikcrtaurvak, not far from Cape Farewell, 

 in Old Greenland. On account of its near resemblance to Yt- 

 tertantalite, it was referred to that species, until Haidinger, by 

 a careful survey of its crystals, proved it to be a new species. 

 Being analysed, it afforded to me the following constituent parts : 



99.65 



The proportion of the oxygen of the bases is to that of the 

 acids nearly as 2 : 1. This relation, although not jicrfcctly cor- 

 rect, is as much so as could be expected from the analysis of so 

 compound a mineral. Hence if we consider the combinations of 

 ' Tantahc acid, and oxide of tin with zircon earth, oxide of ura- 

 nium and iron, as accidental mixed paits, there results for the 

 Fergusonite the following formula : — 

 ye -k "• 

 Ce^ jT« 



The Fergusonite, therefore, differs from the yttrotantalite, in 



• For the details referred to above, we must refer to Dr liischolTs va- 

 luable work. 



+ From the Vetcuskaps Academiens Handlingar, Jahrg, 1828. 



