ORDEil I. KHOMBOHED11AL FLUOR HALOIDE. 75 



ter generally more easily obtained. The aspa- 

 ragus-green varieties from Salzburg, imbedded 

 in talc, shew very smooth faces of cleavage, par- 

 ticularly in the direction of P + &> which, how- 

 ever, are interrupted by conchoidal fracture. 

 Fracture conchoidal, more or less perfect, uneven. 



Surface, the dirhombohedrons and pyramids ge- 

 nerally very smooth. P 1, sometimes rough, 

 though even, sometimes horizontally streaked. 

 R oo frequently a little curved or uneven. The 

 vertical prisms often deeply striated in a longi- 

 tudinal direction. Sometimes all the edges are 

 rounded. 



Lustre vitreous, inclining to resinous. Colour 

 white, though not general. Frequently violet- 

 blue, mountain-green, or asparagus-green ; also 

 yellow, grey, red, and brown colours, none of 

 them bright. Transparent, but generally trans- 

 lucent. A blueish opalescence appears upon the 

 faces parallel to the principal axis in some crys- 

 tals, particularly the white varieties. 



Brittle. Hardness = 5-0. Sp. Gr. = 3-225, 

 asparagus-green crystals from Spain ; = 3-180, 

 from Salzburg. 



Compound Varieties. Implanted globular and re- 

 niform shapes : composition imperfect columnar, 

 faces of composition rough. Massive : compo- 

 sition granular, individuals of different size, not 

 impalpable, faces of composition uneven or rough. 



