THE MINERALS OF NEW SOUTH WALES. 183 



PART II. 



NON-METALLIC MINERALS. 



Class I. 



Carbon and Carbonaceous Minerals. 

 Diamond. 



Cheni. comp. : Carbon. Cubical system. The first mention 

 made of the existence of the diamond in New South Wales, 

 which I have been able to find, is one by Mr. E. H. Hargraves, 

 who. in his report, dated from the " Wellington Inn," Guyong, 

 on the 2nd July, 1851, refers to some enclosed specimens of gold, 

 gems, and " a small one of the diamond kind," from Reedy Creek, 

 16 miles from Bathurst. The next record of the occurrence 

 of the diamond in New South Wales appears to have been made 

 by the Rev. W. B. Clarke, in an appendix to his " Southern 

 Gold Fields," published in 1860 ; he records that four were 

 brought to him on September 21st, 1859, which were obtained 

 from the Macquarie River, near Suttor's Bar ; the crystalline 

 form which they exhibited was that of the triakisoctohedron 

 or three-faced octohedron, and one of them had a sp. gr. of 3*40. 

 Another which was received from Burrendong, on December 29th, 

 1859, had a sp. gr. of 3*50. One from Pyramid Creek, crystallized 

 in the hexakis or six-faced octohedron, weighed 9*44 grains, and 

 had a sp. gr. of 3*49. Another was sent to him in August, 1860, 

 which had been found in the Calabash Creek by a digger as far 

 back as 1852. 



Diamonds were found by the gold diggers on the Mudgee Dia- 

 mond Diggings in 1867, but were not especially worked until 1869. 



The diamonds were obtained from outliers of an old river- 

 drift which had in parts been protected from denudation by a cap- 

 ping of hard compact basalt. This drift was made up mostly of 

 boulders and pebbles of quartz, jasper, agate, quartzite, flinty 

 slate, silicified wood, shale, sandstone, and abundance of coarse 

 sand mixed with more or less clay. 



Many of the boulders are remarkable for the peculiar brilliant 

 polish which they possess. The principal minerals found with the 

 diamond are gold, garnets, woodtin, brookite, magnetite, ilmenite, 

 tourmaline, zircon, sapphire, ruby, adamantine spar, barklyite, 

 common, and a peculiar lavender-coloured variety of corundum, 



