260 A. LIVERSIDGE. 



gold is high. Some particles of quartz are also present; the large 

 white spot which occurs near the upper left hand side of the section 

 is the largest of them, there are also others visible in the photo- 

 graph, but most of the white portions are, of course, metallic gold. 

 I need hardly say that the true appearance of this section is very 

 different from that of the illustration — the section itself is of a 

 rich but dull gold colour, with a matt surface; the matt surface is 

 due to the removal of the closely intermingled ferruginous matter 

 by the nitric acid, used for etching the surface. 



On account of the granular or rather spongelike condition of 

 the nugget and the small area of the interlacing gold surfaces 

 exposed in the section, the crystalline structure of the gold is not 

 visible in the illustration, (2 dias.) although it is apparent with 

 higher powers. The polished sections of this and other similar 

 ferruginous nuggets give but little indication of the true structure, 

 for until they are etched they look as if they were of solid burnished 

 gold, with hardly an indication of the spongy structure and of the 

 enclosed foreign matter. The sp. gr. of this nugget section at 

 23° C. is only 15-21. 



Plate ii, fig. 3, shews the internal structure of a nugget from 

 Queen stown, twenty- eight miles from Melbourne ; like the Gipps- 

 land nugget it shows much iron oxide, the very dark parts of the 

 photograph are cavities from which it had been removed by treat- 

 ment with acid, the surfaces of these cavities in some- places show 

 minute imperfect crystals, but usually they are merely pitted. 

 Externally this nugget was water-worn and rounded, the Gipps- 

 land nugget, {Plate io, fig. 1) shows but slight traces of attrition. 

 The patches of gold free from iron oxides are somewhat larger 

 than in the preceding, (see fig. 2) and the crystalline structure is 

 not so minute. Sp. gr. at 23° C. is only 15-02. 



New Zealand Nuggets. — Two nuggets from the Molyneux River 

 were sliced and etched, and the section of one is shown in Plate 1 1, 

 fig. 4-, enlarged 3 diameters. Both of them appeared massive and 

 free from any appreciable amount of iron oxide, quartz, etc., but 

 on slicing them they were both found to contain much scattered 



