246 



PHYSIOGRAPHY. 



Harmotome. 



Fig. 226. 



Mons - - - 125 5' P. 



s on s over the summit - 110 26 

 s on al 171 4 



s on a2 151 35 



s on a3 149 32 



4ona4' 177 28 



Fig. 224. Primary form, with the solid angles trunca- 

 ted, a on a =121 57' 56'. a on a over the summit, 

 =86 36'. 



Fig. 225. s on T = 123 41' 24". 



Cleavage, parallel with M and T ; also with the planes 

 a ; but imperfect in all directions. Fracture uneven, im- 

 perfectly conchoidal. Surface, a and s streaked parallel to 

 their common edges of combination. M and T smooth, 

 but in most cases T is divided into four faces, meeting at 

 very obtuse angles, as in certain varieties of Fluor. 



Lustre vitreous. Color white prevalent, passing into 

 grey, yellow, red and brown. Streak white. Semi-trans- 

 parent . . . translucent. 



Brittle. Hardness =4-5. Sp. gr. =2-392. 



