ORIGIN AND MODE OF OCCURRENCE OE GOLD-BEARING VEINS. 145 



Beauty reef, and the following sketch, taken from the same source, 

 will show the distribution of the richest parts of the stone. 



It will be seen in this claim again that the richer stone is 

 confined to certain belts of rock, but at the same time certain 

 junctions of lodes occur along which rich deposits of gold have 

 been found. 



South Australian Gold Veins. 



South Australia, including the Northern Territory, comprises 

 a very large tract of country, inasmuch as it extends right across 

 the Continent of Australia from south to north, being bounded 

 on the east by Yictoria, New South Wales, and Queensland, and 

 on the west by Western Australia. Gold veins exist in many 

 places throughout this tract, and comprise many of the different 

 modes of occurrence of such veins, but much of the country is but 

 partly known and very little prospected as yet. 



In the hills about Adelaide, the capital of the Colony, quartz 

 veins carrying gold occur and some of them are being worked ; 

 they exist in sedimentary rocks possibly of lower silurian or 

 pre-silurian age, in various metamorphic rocks such as mica 

 schist, &c, and dykes of coarse granite and other igneous rocks 

 intersect the country. The quartz veins are somewhat similar 

 to those of Yictoria and N. S. Wales, a large amount of iron 

 pyrites occurring in many of them. 



One of the most interesting districts in the colony is that of 

 Waukaringa and Tetulpa, and as a reefing country I am sure it 

 will yet become much noted. 



The country consists in that part of large open plains, covered 

 with salt-bush, and having barren-looking hills as ridges crossing 

 them. Highly tilted and partly altered sedimentary rocks 

 comprise the formation. The rocks are possibly early palaeozoic,, 

 and they become more and more altered as you travel eastward 

 until they pass into mica schists. Along the ridges and across 

 the plains are to be seen numerous quartz reefs intersecting the 

 strata and continuing on their course for miles. 



The fact that very little alluvial covers the rock on the plains,, 

 and that it therefore shews in many places quite bare, enables 

 the quartz veins to be easily followed on their strike across the 

 country. These veins are auriferous, and some of them have 

 been and are being worked. One of these, called the " Alma 

 Reef," is a large vein, having two parallel veins that sometimes 

 run quite close to it, only a foot or so being between them, and 

 at other places diverge from it to some hundreds of feet. 



The Alma Reef can be traced for about ten miles across the 

 country • most of the way it runs along near the top of a hill and 

 its sloping" continuation as a low ridge. At one place, where 



J— September 7, 1887. 



