492 ON THE B1NGERA AND MXTDGEE DIAMOND-EIELDS. 



vary from colourless to pale yellow and green. Their specific gra- 

 vity is 3-42, that of the Mudgee diamonds being 3-44. 



In all parts of the world where the diamond is found it seems to 

 occur in sandstone regions, associated with basaltic rocks, and usually 

 in a drift or conglomerate. This statement applies to India, Russia, 

 Borneo, Brazil, and Africa. The true source of the diamond has evi- 

 dently not yet been ascertained ; for in all the cases mentioned the 

 sources may be regarded as secondary. 



