274 



Notice of some Recent 



[April 



99-70 



100-30 



100-15 

 (Poggendorff, xxviii. 156.) 



24. Voltzite. — This mineral is found at Pont Gibaud, in 

 Puy de Dome. It possesses a pearly lustre ; colour rose- 

 red, or yellow; granular; fracture irregular; softer than 

 glass ; sp. gr. 3*66. It consists of 



Sulphuret of zinc . . 82-92 

 Oxide of zinc . . . . 15*34 

 Peroxide of iron . . . 1*84 



(Poggendorff, xxxi.) 100- 10 



25. — Carbonate of lead and zinc comes from Mount Poxi, 

 in Sardinia, in the form of small crystals, irregularly grouped 

 together in rock quartz ; white and translucid ; hardness 

 equal to calcareous spar; sp. gr. 5*9. It contains 

 Carbonate of lead, with traces of chloride of lead 92*10 



Carbonate of zinc . 7-02 



(Jahrbuch, 3d, 1833, p. 335.) 99*12 



26. Gahnite, according to the analysis of Abich, consists 

 of Silica . . . 3*84 



Alumina . . 55*14 

 Magnesia . . 5*25 

 Peroxide of iron 5*85 

 Oxide of zinc 30*02 



100*10 

 The specimen was from Fahlun. 

 27. Blue Arseniate of Copper, (Jahrbuch, 1st, 1833. p. 73.) 



