380 PHYSIOGRAPHY. CLASS II. 



Hardness = 55... 6-0. Sp. Gr. = 3-826. 



OBSERVATIONS. 



1. The present species consists of oxide of titanium, like 

 the preceding one, but it is purer itself, and also the colours 

 of the fluxes, as obtained by the action of the blowpipe, are 

 purer. 



2. The only mode of occurrence of pyramidal Titanium, 

 ore in nature is in narrow irregular veins, consisting of those 

 species which constitute the rocks themselves, and it is ac- 

 companied by Albite, rhombohedral Quartz, several species 

 of Talc-mica and Augite-spar, prismatic Axinite, arid Crich- 

 tonite. Its chief localities are Bourg d'Oisans in Dauphiny 

 and Switzerland ; but it has been found also in Cornwall, 

 in Norway, in Spain, and Brazil. 



GENUS II. ZINC-ORE. 



Red Zinc or Red Oxide of Zinc. JAM. Syst. Vol. III. 

 p. 447. Prismatic Zinc-Ore. Man. p. 235. Red Oxide 

 of Zinc. PHILL. p. 353. Zinkoxyd. LEONH. S. 312. 

 Zinc oxide' ferrifere lamellaire brun rougeatre. HAUY. 

 Traite', 2de Ed. T. IV. p. 179. 



Fundamental form. Scalene four-sided pyramid. 

 Vol. I. Fig. 9. 



Cleavage, P -f- oo 125* (about), distinct ; less 

 distinct, Pr-f ooandPr-|- oo, traces of (Pr-f oo) 5 . 

 Fracture conchoidal. 



Lustre adamantine. Colour red, inclining to yel- 

 low. Streak orange-yellow. Translucent on the 

 edges. 



* According to Messrs BREITHAUPT and PHILLIPS, this 

 angle is = 120, and the prism in combination with Pr + w a 

 regular one. H. 



