ORDER II, RHOMBOHEDRAL ZINC-BARYTE. Ill 



2. RHOMBOHEDRAL ZINC-BARYTE. 



Rhombohedral Calamine. JAM. Syst. Vol. II. p. 440. Man. 

 p. 66. Carbonate of Zinc. Calamine. P;, ILL. p. 355. 

 Galmei (in part). WERN. Hoffm. H. B. IV. 1. S. 96. 

 Galmei. HAUSM. 1. S. 345. Zinkspath. LEOXH. S. 315. 

 Zinc carbonate'. HAUY. Traite', T. IV. p. 164. TabL 

 corap. p. 103. Traite', 2de Ed. T. IV. p. 181. 



Fundamental form. Rhombohedron. R =r 107 

 4<y.* Vol. I. Fig. 7. WOLLASTON. 



a = Jl-95. 

 Simple forms. R oo (o) ; R 1 (g) = 137 



8'; R(P); R + 2(wi) = 6629'; P + CD(M). 

 Char, of Comb. Rhombohedral. 

 Combinations. l.R. P+GD. Sim. Fig.llS. Siberia. 



2. R QD. R. R + 2. Sim. Fig. 115. Rezbanya, 

 Hungary. 



3. R. R + 2. P + oo. Rezbanya. 

 Cleavage. R, perfect, often curved. Fracture, 



uneven, imperfect conchoidal. Surface ; R 

 generally curved, and often rough. The other 

 forms frequently a little more even. 



Lustre vitreous, inclining to pearly." Colour 

 white, frequent, though seldom pure. Generally 

 grey, green, or brown. Streak white. Semi- 

 transparent ... translucent. 



Brittle. Hardness = 5-0. Sp. Gr. = 4-442, a 

 honey-yellow crystallised variety from Aix-la 

 Chapelle. 



* Mr PHILLIPS gives this angle = IOC' 30 7 , which would 

 make a = * 2-055. 



