The New York herald. [volume] (New York [N.Y.]) 1840-1920, 1869-10-25

Otago and In westland, being derived from rocks
when are never auriferous In the south, bus
which nave been locally metamorphosed by being
involved In complicated disiocatons OF this part OF
the earths crust, accompanied by the Injection OF
infer that the gold and other metals found in this
rich mineral district have been introduced through
their agency. Turning now to the North Island we
ma an extensive area, about one-thtrd OF the whole,
occupied by the unaltered paleoz0ic strata which
overlle the metamorphic rocks or south lie th en-
pointed out on geological map the distribution OF
these rocks, indicating those portions OF the map
derived from actual observation The rocks comprise
sand stones and states, frequently much induraed
ana dlsJolnted, but no trace OF true metamorphc
rocks have yet been discovered In the North Island.
Gold had been found In the Thames dis
which are almost at the two extremiries OF
the island, and doubtless many intermediate
places WIN yet be discovered: He then described
ern side OF which the gold fields are situated and
exhibited map showing the position and compare
tive area OF each, calling attention the very inslg-
niicant portion OF the country which had as yet
been tested by the miners. The rocks found IN the
Peninsula consist OF lofty ridges OF the slate rocks,
interbedded with which occur strata formed from
very ancient eruptiye rocks. Enveloplng these
ridges TO a height above the sea OF many hundred
feet deposits OF tertiary tufa stratlhed rock
consisting OF volcanic ash mtermixed with elected
fragments Of recent geological date. This tuiaceous
rock presents very marked variety in its character,
In some localities forming gray hne grained rock
containing large quantity OF aurferous pyrltes
dispersed through Its substance. This Is the char
acteristlc rock in Which all the richest lodes
have been found at the Thames. In all the aurlie-
rous areas yet examined gneous dykes occur, the
composition OF which shows that they are allied 10
those found accompanying the dlslocations prevl-
ousy alluded to as occurring In the South Islands,
and which no doubt account for their presence III
these superficial rocks He then proceeded to de-
scribe the hills between Wellington Har0or and Cape
1erawiti, in which district aliuvial gold has been
found In small quantities, and showed that they
consist or the slate aud sandstone rocks ana
that we have neither the metamorphic rocks OF the
South nor the gneous dykes of the North to account
for the occurrence OF this gold. In every case,
however, where the gold mas been found II Is
rock, patches OF which occur in lines not
agreeing with the stratiilcation. This rock is a
frlaDle cherry slate OF deep indigo blue
color, traversed by innumerabe tnread-like
veins OF quartz. In the neighborhood Of
this rock the sandstones are highly indurated and
mfitrated with silica, so that IN some cases hard
specimens have been mistaken by good authorities
for fine grained granite. We have therefore, an in
dication OF chemical change IN these rocks, and
from observation ID found that the patches Of rock
so altered conform to lines OF dlslocaton parallel
with those which are found to occur In the NeisOn
area. From the foregoing considerations we find
that in the south, where the gold Is most widely
spread we have the metamOrpnic rocks on the sur
face; In Nelson, disIocations, igneous dykes and
rocks locally metamorphosed; OF the Thames, ig-
that in the three latter cases we have evidence that
the existence Of q communication between deep
seated and acknowledgement rocks ana the surface
Is the essential accompaniment OF the gold. He
mentioned, In conclusion, that thermal waters e5-
Gaping by such lines OF communication are generally
admitted sufficient to effect the transport OF any
metal