HEM1TROPE AND INTERSECTED CRYSTALS. 91 



' 



Fig. 119. 



The staurotide affords a good example of this 

 variety of form. 



The primary form of the staurotide is a right 

 rhombic prism, fig. 119. 



Fig. 120. 



Two of these prisms frequently cross each other at 



right angles as in fig. 120. 



. 



Fig. 121. 



And sometimes at an oblique angle as in fig. 121. 



In other minerals it is sometimes observed that 

 three, four, or more crystals, intersect each other in 

 this manner, and produce figures apparently remote 



M 2 



