



Secondar 



PHYSIOGRAPHY. 



Apatite. 



31 



Secondary form. A thin, six-sided prism derived from a rhombic 

 prism, through the truncation of the acute edges. 



Cleavage parallel with the lateral planes of the primary form, and 

 with its shorter diagonal. 



Fractare scarcely observable. 



Surface uneven. 



Lustre pearly, inclining to adamantine. Color greyish-white. 

 Translucent. 



Sectile. Thin laminae are flexible, like Talc. 



Hardness = 1-0 . . . 1-5. Sp. gr. = 4-025. 



1. Before the blow-pipe, it conducts like white Antimony. A copious 

 precipitate of oxide of antimony is thrown down from its solution in mu- 

 riatic acid, by water. 



2. But two specimens of this mineral, the one at Dresden and the other 

 at Halle, have been seen ; and their locality is unknown. 



APATITE. Rhombohedral Fluor-Haloide. 



MOHS. 



Primary fonrio Regular hexagonal prism. 

 Secondary forms. 



Fig. 32. 



Fig. 33. 



M 



M 



M 



M on a? 

 P on x 

 x on x 



M on e 

 M on r 

 P on r 



129 13' 53") 



140 46 7 V 



143 7 48 ) 



150 00 00 



112 12 28 



157 47 32 



