258 A. LIVERSIDGE. 



Copper Nugget from Bolivia, (Plate 9, fig. 5 ) — This specimen 

 is water-worn and massive although it contains a few cavities and 

 fissures. The crystalline structure is well developed in parts, 

 many of the crystals show an elongated or prism-like section, 

 although copper crystallises in the cubical system — this prismatic 

 or platy form is often seen in gold nuggets. Sp. gr. 8 - 64 at 24° C. 



Copper Nugget , Burr a Burr a, South Australia, (Plate 9, fig. 6) — 

 This specimen is but little, if at all waterworn, internally it con- 

 tains fissures and cavities, and some of the crystals are seen to 

 radiate from various points ; mainly to the circumference. The 

 fissures etc., look as if the nugget had been formed in much the 

 same way as an agate, i.e., that the copper has in this case been 

 deposited within a cavity which it has more or less completely filled. 

 The exterior of the mass is granular with, perhaps, traces of 

 crystals. Sp. gr. 8-22 at 24° C. 



As in the case of the gold and platinum nuggets, there is every 

 indication of the silver and copper nuggets having been deposited 

 from solution, and nothing to indicate that they have undergone 

 fusion, either igneous or hydrothermal. 



