60 APPENDIX. 



these and other regions in which the diamond is found. Drift 

 or alhivial cinnabar is not less remarkable than drift diamonds ; 

 and I believe at present no lode has been detected. 



In California cinnabar is said to be brought up by Solfatara 

 action. {Phillips, in Phil. Mag., Dec. 1868, p. 431.) It may, 

 therefore, be that the Cudgegong mineral is due to the action of 

 former hot springs. The account given by Mr. A. Phillips re- 

 specting the " Chemical Geology of the Grold Fields of California" 

 in the paper cited above, justifies the further inference that 

 silicated waters may also have operated in coating and cementing 

 pebbles and fragments of rocks at Cudgegong as they have done 

 in California. He even shows that quartz veins holding gold, 

 and coloured by pyrites, as Avell as auriferous pyrites itself, have 

 been formed in recent times by the action of aqueous solutions. 



Diamonds in Borneo and Afeica. 



There are but two other countries to which I need refer, — 

 Borneo and Africa. 



In the soutliern ravines of the Rotos Borneo chain, which is 

 composed of serpentine, diorite, and gabbro, which run north 

 and south, there is a deposit of red clay, with fragments of quartz, 

 in which spangles of gold, magnetic iron, platinum, and also 

 osmium and iridium, are met with, the whole reposing on serpen- 

 tine. In this clay, on the ivestern slopes, diamonds are found over 

 fragments of syenite and diorite, and vidth the ores above named. 

 Black quartz with pyrites and plates of platinum are there the 

 iadications of diamond, and, according to M. Louis Horner, this 

 quartz belongs to the serpentine. (See d' Archiac, ii, 333.) 



So varied, yet to some extent so consistent with each other, 

 are facts connected with the history of the diamond. That its 

 mode of production in all countries may have been the same is 

 very probable ; but that origin, it must be said, obtains little 

 illustration from the various geological conditions with which it 

 is associated. Perhaps this very variety, whilst setting dogmatism 

 at defiance, may serve as encouragement to the close observation 

 of practical prospectors. 



Of African diamonds we have only heard much of late. 

 Knowing that they are generally found with gold, and that 

 Africa contains numerous auriferous regions, it might have been 

 anticipated that diamonds would have had a greater celebrity in 

 that vast country, forming a quarter of the globe, than they 

 have had in modern times. 



But though Heeren has shown that there was a considerable 

 trade among the ancient Carthaginians in diamonds brought 

 from the interior of Africa, the only record I can find in modern 

 times of the existence of diamonds in that part of Africa, is of 



