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New Zealand, drawn to the same scale, placing the Otago Mica-schist area 

 directly over that of Gippsland, and making the meridians parallel, that there 

 is a wonderful coincidence between the relative position of the goldtields in the 

 two countries, the chemical character of the gold, and the nature of the asso- 

 ciated rocks and minerals. 



New Zealand, thus compared, equals in length from Gippsland in Victoria, 

 to Rockhampton in the north of Queensland, a range of territory which is im- 

 portant to the question of relative mineral wealth, when we also observe 

 that New Zealand covers in width the mineral bearing ridge or Cordillera of 

 Eastern Australia, having the ocean on the west instead of the Murray 

 plains, and on the east only small areas of the carboniferous rocks. 



By referring to the accompanying map (Plate 21), in which the relative 

 extent and position of the two countries is shown at a glance, it will be found 

 that the chief Victorian diggings, such as Ballarat, Castlemaine, and Bendigo, lie 

 altogether west of the New Zealand boundary, and this is quite in accordance 

 with the absence of any geological formation in New Zealand similar to the 

 highly-cleaved Silurian strata of those gold fields. Then selecting for com- 

 parison the chief diggings in both countries, we find that Beech worth, Snowy 

 Creek, and Omeo, correspond exactly in area and position with the richest 

 diggings of Otago. Ophir exactly covers the position of the chief Hokitika 

 diggings ; while the Bathurst district has its analogue towards the south of the 

 Teramakau. Bingera lies a little to the north of the Nelson gold fields, and 

 the Rocky River diggings cover those of the Wakamarina. Continuing north- 

 wards there is a long gap without auriferous localities in both countries, till we 

 are struck by finding that Gympie creek, in Queensland, exactly agrees with 

 the Thames diggings. With more perfect maps of Australia than those at my 

 command, and especially one showing the geological formations, it might be 

 interesting to follow the analogy into its minute details, and so far as I am 

 able to judge from the information I possess, it would be fully borne out. 



From the description of the New South Wales gold fields, by the Rev. 

 W. B. Clark, I gather that in the southern portion of the Coi-dillera, the gold, 

 which is of good quality — containing less than 6 per cent, of silver — is chiefly 

 found in that part of the country composed of Hornblendic gr^anite and Mica 

 schist ; and this, as before stated, corresponds with the general character of the 

 Otago country. 



In what he terms the western district, which on our map corresponds with 

 the Nelson district in New Zealand, he describes it as characterised by irre- 

 gular areas of Hornblende granite, with locally transmuted members of the 

 upper Palaeozoic group, and Serpentine charged with Chromic iron, where 

 the rocks have been altered by dykes of Diorite. This description is quite 

 applicable to the Nelson district, and, moreover, in both districts the gold is 

 found to be alloyed with from 10 to 14 per cent, of silver. At Cympie creek, 

 in Queensland, we learn from reports by the Government geologists, that the 

 gold is obtained from reefs traversing decomposed Diorite rocks, associated 

 with masses of tufaceous Breccia and Conglomerate. Areas of soft felspathic 

 schist also occur, the whole series of formations being intersected by dykes of 

 Diorite. From a collection of the rocks of this district, lately sent to the 

 Museum by Mr. T. Hacket, I select many that cannot be distinguished from 

 Thames specimens : the quality of the gold is also identical, and highly charac- 

 teristic, as it contains over 35 per cent, of silver, and is found along with small 

 quantities of lead, arsenic, antimony, copper, and other metals. Among the 

 rock specimens it is interesting to find some taken from mines at Gympie 

 Creek, that from their appearance at a first glance, and also from their chemical 

 composition, would be classed as Diorites, yet distinctly containing fossils of the 

 same species that characterise our upper Palaeozoic and Triassic rocks. 



