160 PHYSIOGRAPHY. 



Cupreous Anglesite Cupreous Bismuth. 



Secondary form. 



MonT 102 45' w 

 P on /I 90 00 / 



T on /I 161 30 I jj 



M on d 120 30 ' p 



Cleavage, parallel to M and T very perfect. Surface 

 generally smooth and shining, some of the faces rough. 



Lustre, adamantine. 



Color deep and beautiful, azure-blue. Streak, pale blue. 

 Faintly translucent. 



Rather brittle. Hardness =2-5 . . . 3-0. Sp. gr.=5-30 

 , . . 5*43. BROOKE. 



1. Analysis. 

 By BROOKE. 



Sulphate of lead ... 74.4 



Oxide of copper ... jg.0 



Water 4-7 



2. It is found along with other ores oT lead, at Lead Hills in Scotland : 

 also at Linares in Spain. 



CUPREOUS BISMUTH. Prismatoidai Poly- 

 poi o n e - Gl an c e . 



Crystalline. Primary form not known ; probably pris- 

 matic. Massive : composition columnar, the individuals 

 being long and slender ; also impalpable. 



Cleavage, in one direction parallel with the prismatic 

 axis. Fracture uneven, or imperfectly conchoidal. 



Lustre metallic. Color steel-grey, light copper-red, 

 passing to yellowish. Streak blackish grey. 



Hardness =2-0 . . . 2-5. Sp. gr. =6-125. 



1. It melts very easily before the blow-pipe, coloring the flame of the 

 lamp, blue ; and leaving, after the fumes have subsided, a whitish, or sul 



