23 



and silver, sometimes occurs crystallised iu the form of cubes. (Jase 48. 



Owing to the softness of the metal, these crystals generally 



lose their shape by being knocked about in the beds of the 



streams, and are but rarely preserved. One such has been 



presented to the Museum. It is a somewhat damaged cuhe, the 



longest side of which is 4 millimetres (about -~^ inch) long ; the 



corners are truncated by the octaliedron (9293). 7658 consists 



of native gold and native platinum in intimate association. At 



a higher level than the leads now being worked there is an 



older drift, also containing gold and platinum in small quantities. 



It is believed that the newer leads have been formed from the 



debris of the older ones. 6683, 9292, each containing platinum 



and gold, illustrate the older drift. 6662 shows the contact 



between the pebbly drift and the decomposed bed-rock. 6664, 



decomposed bed-rock, into which grains of platinum have been 



wedged. 6665, aTnodule of magnesite in which is embedded a 



grain of platinum. This nodule is, in all probability, of 



secondary origin, and has formed round the grain of platinum. 



An analysis of the crude platinum shows it to contain 76 per 



cent, platinum, 1'3 per cent, of iridium, I'B per cent, of rhodium, 



9"3 per cent, of osmiridium, 10"15 per cent, of iron. 



9480 : platinum obtained from the alluvial workings (gold) at 

 Warraderry, near Grenfell. 



Specimens of iiussian platinum will be found in show-case 77. 



MERCURY. 



Mercury — or quicksilver, as it is commonly called — is some- 

 times found in the form of metal, but more generally has to be 

 extracted from its combination with sulphur as the mineral 

 cinnabar. Specimens of native mercury will be found in case 77, 

 more particularly 8410 from California. 



Although ores of mercury have been found in New South 

 Wales, Queensland, Victoria, and New Zealand, it has not as 

 yet been profitably mined. The demand for quicksilver in the 

 amalgamation of gold ores would render the discovery of a 



