372 Scientific Intelligence. 



Br Wernekingk is of opinion, that this mineral is a variety of the Cron- 

 stedtite of Steinmann, at least in so far as may be inferred from the descrip- 

 tion given by Zippe of the latter mineral. He described Sideroschisolite as 

 occurring in small simple three-sided and six-sided pyramids ; the former 

 resembling tetrahedrons, fixed to the support with their most acute solid 

 angle or apex, and showing a perfect cleavage perpendicular to the axis, 

 the face of crystallization parallel to it being smooth, the inclined faces of- 

 ten convex. These forms would be analogous to the hemi-rhombohedral 

 ones of tourmaline and red silver ore. They are sometimes grouped with 

 divergent axes. The hardness is between 2.0 and 3.0, (gypsum and cal- 

 careous spar) ; the specific gravity probably above 3.0. Before the blow- 

 pipe, it melts easily into a black magnetic globule ; thin laminae of the 

 mineral, exposed to the flame of a candle, become iron-black and mag- 

 netic. Exposed to nitric acid, they become white and keep their form, 

 but show a gelatinous consistency when touched. 



The sideroschisolite occurs along with conchoidal magnetic pyrites and 

 sparry iron at Conhonas do Campo, in Brazil. (Poggendorff's Ann. der 

 Phys. 1824. 8. p. 387.) 



25. Analysis of Uranite by Berzelius. 



Baryta 



Lime 



Oxide of Copper 



Magnesia and Manganese 



Oxide of Uraaium 



Phosphoric Acid 



Water 



Foreign Admixtures 



The variety from Autun showed, besides, traces of fluoric acid and am- 

 monia, that from Cornwall arsenic acid and fluoric acid. The chemical 

 formulae given by Berzelius are for the varieties 



From Autun - Ca3 P2 + 4 U P + 48 Aq. 



From Cornwall - Cu3 P2 + 4 V P + 48 Aq. 



They differ in their ingredients of lime and copper. Berzelius proposes 

 to apply in future the name of Chalcolite to the variety from Cornwall, in 

 order to distinguish it as a particular species from the French variety, for 

 which he retains the name of Uranite. He says, " Since, according to 

 Mitscherlich's excellent discovery, lime and oxide of copper are isomor- 

 phous bodies, they must assume the same form of crystallisation, if com- 

 bined with the same number of atoms of oxide of uranium, phosphoric 

 acid, and water, and therefore remain only one mineralogical species in the 

 eyes of those who take no notice of any thing but the crystalline forms, 

 which, however, cannot be allowed to be just, when viewed from the che- 

 mical side of the question." It may be added, that not only the forms, 



