Anniversary Address. 31 



colourless, diaphonous, smooth and very bright with 42 triangular 

 facets. One was broken in two. 



Thirty-seven others were taken, the last in July 1833, from the 

 Adolphskoi Mine and were used by the Countess Poller in 

 decoration of her church images- One weighed f of a carat. 

 Their forms showed from 12 to 42 curved facets, smooth and 

 sparkling. In 1831, however, a few were found in the gold land 

 of M. Medjer near Ekatherinburg. One was given to the 

 Institute of Mines by his son, after the father's death. It was a 

 rhombhoidal dodecahedron with rounded edges and translucent, 

 weighing -| of a carat. (Bidl. Oeol. Soc. de France, IV., p. 100, 

 1833.) The information here given was received from Count 

 de Cancrine, ^Russian Minister of Finance. 



Sir Eoderick Murchison, in 1841, saw forty diamonds from the 

 Adolpskoi rivulet ; but as the gold found with them did not pay, 

 no further search was made for diamonds. Three other localities 

 have also been named, (" Oeol. of Hussia and the Ural, 1845," p. 

 641,) in two of which one diamond and in the third two diamonds 

 were found- 

 Sir Eoderick considers that the Itacolumite of Brazil occurs 

 in various parts of the Ural, where it was detected by Colonel 

 Helmersen, and adds what seems to bear upon certain conjectures 

 previously mentioned. He says : — " We may add that as 

 Carbonaceous grits of the Devonian and Carboniferous periods 

 exist, it is very easy to conceive how these masses, like other 

 sediments to which we have previously alluded, have been 

 transmuted into the quartzose micaceous schists which occur in 

 the Chain, and how the diamonds have been derived from them 

 and deposited in the auriferous gravel." (p. 482.) 



Finally, I may remark that Osm-iridium found on the 

 Cudgegong occurs in three places near the Ural, as weU as in 

 South America and in Canada, in gold diggings with which 

 diamonds are, as we have seen, generally associated. Moreover, 

 Cinnabar found on the Cudgegong is also associated with the 

 diamond detritus of Brazil ; and as the mode of its occurrence is 

 precisely that in which it presents itself in the Grilbert gold-field 

 of jS'orth Queensland (as I learn from Mr. Daintree), and also in 

 that most wonderful gold-field on the River Thames in New 



