74 



PHYSIOGRAPHY. 



Blue Malachite. 



gle planes. 6. Form 4th 3 with lateral solid angles replaced 

 by single planes. 



Fig. 68. 



PonMorM' 



MonM 



P on a 



P on el or e'l 



P on e2 or e'2 



P on e3 or e'3 



P on e4 or e'4 



Pon/or// 



Pon A 



M or M' on a 



M on el or M' on e'l 



M on e2 or M' on e'2 



M on e4 or M r on e'4 



M on e5 or M' on e'5 



M on e6 or M' on e'6 



M on /or M on/' 



Cleavage parallel to M and M' perfect; parallel to P 

 very difficult. Cleavage may be effected also parallel with 

 both diagonals of the primary form. 



Surface of P striated in the direction of the longer diag- 

 onal. 



Lustre vitreous, almost adamantine. Color various 

 shades of azure-blue, passing into blackish blue and berlin- 

 blue. Streak blue, lighter than the color. Transparent . .. 

 translucent on the edges. 



