32 



hue. They frequently stand on their edges, or are as it 

 were thrown about in different directions, on various 

 matrices. This is on dark or gray lime-stone, with blend* 

 and galaenaf . The first is confusedly crystallized, which 

 commonly happens ; the latter more regularly so, in cubes 

 with the corners truncated, or a cubo-octaedron, as Hauy 

 rightly terms it. 



The lower figure has smaller crystals, roughish towards the 

 edges, as if not quite finished. The roughness proceeds from 

 the edges of the molecule, or from spaces where there seems 

 something wanted to finish the faces and make the surfaces 

 even. The crystals are somewhat striated towards the 

 centre, and are loosely fixed among light purple fluor and 

 galaena. 



* An ore of zinc called by the miners black jack, 

 t An ore of lead. 



