Mines and Mineral Statistics. 
153 
of tlie strata in the sections of the Carboniferous formation, there 
has arisen a difRculty in collating the gold deposits with tliose of 
Victoria ; and, in tins respect, at present the upper deposits in 
the former province have not been assigned with much precision 
to the epochs adapted by Mr. Selwyn for the latter. And it also 
follows that his view of tlie distinct ages of Pliocene auriferous 
and Miocene iion-auriferous gravels cannot bo tested in New 
South Wales, if, indeed, it has not already been tested by the 
actual discovery of gold in the so-called Miocene deposits them- 
selves, as they occur in Victoria. 
So far as is at present known, gold in Victoria is derived 
chiefly from the Lower Silurian formation; but researches con- 
ducted for me at II.M. ^lint in Sydney ])roAm that it exists in 
almost every distinctive rock of New' South AVales. In this pro- 
vince the alluvial deposits are not so extensive as in Ahetoria ; 
but this probably arises from the fact previously mentioned of the 
strike being in A^ictoria transverse to tlie direction of the 
Cordillera ; by whicb means the currents Avhich distributed the 
drift had a Avider area of gold-bearing materials to denude than 
in NeAv South AValos, Avhere, I conclude from uumerous examples, 
the principal currents A\'crc to nortliward, so tliatiii that province 
they Avoukl coincide with the direction of the Cordillera, and not 
accumulate the deposits in such low-lying extensive regions as 
those of the Aliirray Districts. The same ohjeclion Avould obtain 
on tbe supposition of gradual AA'aste and accumulation Irom less 
powerful agency than that of a general rush of AA'ater. It is not, 
however, to be doubted that there is an enormous amount of gold 
yet untouched in uumerous places in New South AVales, not only 
in the quartz lodes (or reefs) hut in gullies and plains Avhere 
alluvial gold diggings will yet be discovered. 
Dr. Duncan, in an elaborate paper on some of the fossil Tertiary 
corals of Australia (^Proceed mr/s of the Qcolorjical Augusfy 
1870), suggests the propriety of discarding tlie divisions into 
Pliocene, Miocene, and Eocene, of the Australian Tertiaries, and 
of substituting the general term Kainozoic, since ho considers 
them merelv as successive deposits of one continuous epoch. But, 
as proved by my own researches more than tAventy years ago, 
much of the gold iuNeAV South AV ales is derived from iron pyrites 
in granite, and in beds of sedimentary origin, consisting of 
siliceous matter cemented by iron derived Irom decomposed 
pyrites, whilst it has been shown by A])Hn, Daintrce, Ilacket, 
AVilkinson, and others, that much gold in A^ictoria and Queens- 
land is due to the intrusive agency of felstoues, clvaiiitcs, and 
diorite. The dykes or reefs of quartz in the Silurians are there- 
fore not, as once supposed, the exclusiA'e sources of Australian 
gold. Nay, there is good reason to believe that the Carboniferous 
rocks are themselves impregnated, as in one remarkable instance 
