63 



Cooma; 8531, Dartmoor Mine: gossan from a depth of 20 feet, 

 assaying 24 per cent, of copper, 12|- per cent, of lead, 51 oz. 

 silver per ton. Eicli copper pyrites ores from tlie l^iery Creek 

 Mine are shown. 

 , 10052, Lobb's Hole Mine, Tarrangobilly : copper pyrites. Case 65. 



CoBAB. — This important Copper Pield is represented by a Western 

 variety of specimens, some of great beauty, both in this case and 

 in upright case 43 at the lower end of the room, where the larger 

 ones are placed. The country rock of the district is essentially 

 clay-slate,* and is frequently very ferruginous (8931). Generally 

 speaking, very little copper was showing in the lode at the sur- 

 face. 8940 represents an outcrop of slate charged with copper 

 carbonates. The outcrop is sometimes siliceous (8941). 8939, 

 raddle (earthy oxide of iron), is taken from a native well on the 

 outcrop of the lode.f 



Native copper occurs in small quantities in the upper levels. 

 1753 and 2854 show arborescent forms. See also 1747 in case 

 43. 1843 shows films of native copper between the partings of 

 the slate. 



Cuprite, red oxide of copper, occurs both massive (8176) and 

 crystallised (1761, 1766). The crystals form octaliedra, with 

 angles and edges modified by faces of the cube, quite similar to 

 those from Broken Hill. 



Azurite and MalacMte. — Beautiful specimens of these minerals 

 occur above water-level at Cobar. The crystals of azurite (1787 

 and in case 43) are quite as well formed, if not quite so large, 

 as those from Broken Hill (case 63) . The malachite is the best 

 found in New South Wales, but generally appears in silky 

 aggregates not suitable for polishing. The finest specimen is the 

 large one in a special case close by. 



1809, slate breccia, cemented together by crystallised copper 

 carbonates. 



* It is frequently the case that copper ores are associated with igneous rocks ; this is not 

 so at Cobar. 



t The aboriginals used the raddle as a pigment, and "Cobar" is claimed by them as 

 their name for the material. 



