Serpen line A tea and l\h i/ol ites. 257 



100.15 

 Density - 2.80 



Numerous boulders lie scattered about on the grassy slopes of 

 the serpentine belt ; some are waterworu, and evidently have 

 weathered out of a serpentine conglomerate, to be referred to 

 later. Other blocks, however, are irregular, and appear to re- 

 present portions of the original basic rock of the serpentine. 

 Considerable variety is exhibited by these rocks. Mosit of them 

 are tough pyroxene rocks, showing varying stages of alteration. 

 One type common in the vicinity of the Monument Gap is a 

 coarse-grained rock, extremely tough, and composed largely of a 

 gre^in, rhombic pyroxene, corresponding most closely to bronzite. 

 About a third of the I'ock, however, consists of a hard, white 

 mineral generally somewhat opaque. It is perhaps a secondary 

 felspar, and parts of freshest sections show traces of the repeated 

 twinning of the original triolinic felspar. 



An analysis of this rock by Mr. Ampt is given : — 



