Norman Taylor — The Cudgegong Diamond Field. 455 



(c). Barklyite. — An opaque magenta-coloured variety first discovered in Victoria 

 and named after Sir Henry Barkly. 

 All the above occur in small fragments (larger higher up the river) in great 

 abundance. 

 {d). A variety, locally termed " mouse dung," which it much resembles, is 

 characteristic of the locality. It occurs in six-sided prisms, slightly 

 barrel-shaped or tapering, with flat end faces ; one-fourth of an inch 

 long, and one-twentieth of an inch in diameter ; bluish white, with a few 

 dark blue spots, opaque ; hardness 9 ; specific gravity 3 - 59 ; composition 

 found by analysis : — 



Alumina 98*57 



Ferric oxide 2-25 



Lime *45 



101-27 

 (e). Ruby. — A transparent pink variety, found sparingly in flat grains one-tenth 

 of an inch in diameter ; its shade often passes into violet and blue ; 

 hardness 9 ; specific gravity 3-96 ; composition found by analysis : — 



Alumina 97'90 



Ferric oxide 1*39 



Magnesia "63 



Lime *52 



100-44 

 (/). A few large rolled oval pebbles of corundum have also been noticed, 

 exceeding half an inch, of a mottled dirty wbite and pink colour, per- 

 fectly opaque. From their low and variable specific gravity (3-21 to 

 3-44 and upwards) they appear to be impure massive forms of the 

 mineral, and possess the requisite hardness. They look like jasper 

 pebbles, and are probably what are termed "morlops" by the Bingera 

 miners. Their specific gravity accounts for their association with the 

 diamonds in washing off. 

 Quartz. — Opaque double hexagonal pyramids, one-eighth to one-fifth of an inch 

 in diameter, are very common. Quartz pebbles occur of all sizes. The 

 varieties comprise agate of poor quality, carnelian, jasper, rock crystal, 

 smoky quartz, amethystine quartz (rare), and a bluish opaline variety. 

 Fragments of grey quartz, imbedding felspar, derived from the granite 

 of Aaron's Pass, 40 miles up the river, are common. A geode of 

 chalcedony, having the cavity filled with quartz crystallized in rhombs, 

 was also found. 



Having thus fully described the geology of this diamond field, 

 and seeing that the diamond occurs in an old river drift, we are 

 led to inquire whether the diamond has been drifted, like the other 

 minerals with which it is associated, and, if so, which of the forma- 

 tions — Igneous (granite, greenstone, basalt, etc.) or Sedimentary 

 (Upper Silurian, Devonian, Carboniferous or Mesozoic) — has afforded 

 it ? or, has the diamond grown in the older drift in which it is now 

 found ? 



Diamonds were first reported by the late Eev. W. B. Clarke 

 (Southern Gold-fields of New South Wales, page 272) from the 

 Macquarie Eiver in 1860. On this river, at Suttor's Bar, they were 

 worked contemporaneously with the Cudgegong, but, owing to 

 heavy floods, little could be done. The Bingera field was reported 

 on by Professor Liversidge in 1873 (Mines and Mineral Statistics of 

 New South Wales, 1875, p. 104). 1 The Borah Creek (a tributary of 



1 See also, Liversidge, Quart. Journ. Geol. Soc. 1875, vol. xxxi. pp. 489-492. — 

 E. E., jun. 



