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THE NEW ZEALAND GAZETTE.

a. Gneiss and Granite Zone.—The western
shores of Blind Bay, from Separation Point
to Riwaka; consist of granite, bordered on
the eastern side opposite to the Tata Islands
by gneiss. This same zone of granite and
gneiss may be traced in a southerly direction
up the Motueka river to the confluence of
the Wangapeka, and is cut through by the
Buller river, where it enters the gorge of the
Devil's Grip on the western ranges, and
extends all along the eastern slope of the
mountains as far as the Rotorua lake.

b. Zone of Hornblende-schiet and Crye-
talline Limestone (Urkatk).—Proceeding
from the granite and gneiss towards the
west, we next meet, on the top of the Piki-
kerunga range, between Riwaka and Takaka,
a broad zone, on which hornblende-schists,
quartz-schists, and crystalline limestone
succeed one another in regular and numerous
alternating strata, with a vertical dip, and a
strike nearly due north and south. This
formation continues in a westerly direction
to the opposite side of the Takaka valley,
where it is broken through by erupted masses
of diorite-porphyry and serpentine, which
show themselves in the Stony creek and
Waingaron. The same zone of crystalline
schists exhibits itself in the steep escarpments
of the gorge of the Wangapeka. A charac-
teristic feature of this limestone formation
is the existence of numerous funnel-shaped
pits, which have been hollowed out by the
action of water, which has dissolved the
limestone.

The interesting phenomenon of the Wai-
karomumu springs in the Takaka valley,
where whole rivers suddenly appear on the
surface with the water bubbling, is readily
explained by a subterranean passage of the
water through the limestone from the ranges.
This crystalline limestone on the ranges must
not be confounded with the other limestone
in the Takaka valley, which belongs to the
tertiary period.

c. Mica-schist and Quart--schist.—The
crest of the western ranges, with peaks
rising to an altitude of about 6,000 feet, the
Anatoki mountains, Mount Arthur, and the
chain lying between the source of the Wa-
ngapeka river and the Buller river gorge,
consists of mica-schist containing garnets,
alternating with quartz-schists.

d. Zone of Clay-slate.—Still proceeding
towards the west, the mica-schists pass by
insensible gradations into clay-slates, which,
however, still exhibit the same alternating
strata of quartz-schist. The Aorere valley
and the lofty peaks on its eastern side, as
the Slate river peak, Lead Hill, Mount
Olympus, and the Haupiri range, generally
belong to the clay-slate zone. In all those
ranges the strata are more or less vertical,

and exhibit unmistakeable signs of greet
disturbance at former geological perioda,
For instance, Mount Olympus presents the
peculiar appearance of strata diverging from
below towards the serrated edge of the
mountain like the folds of a fan. A similar
disposition of strata is observed on the lofti-
est summit of Europe, namely, on Mont
Blanc.

GOLD.

In the mica-slate and clay-slate zone of
the western ranges, we have the matrix of
the gold. From the interest attaching to
this subject, I may be allowed to repeat the
limits of these gold-bearing formations. On
the east these formations are bounded by
the Takaka valley; on the west by the
Aorere, valley, so that its breadth is from
fifteen to twenty miles, and includes the
Anatoki and Haupiri ranges. In a southerly
direction the same formations can be traced
to the gorge of the Buller river. How much
further it extends in that direction has not
yet been ascertained; but, inasmuch as gold
has been found at the northern extremity of
the Southern Alps, and also in the gravels
of the Mataura, in the Province of Otago,
towards the southern extremity of the back-
bone, it is not unreasonable to infer that the
same gold-bearing zone may extend contin-
uously throughout the whole length of the
Middle Island.

Before speaking more specially of the
gold-fields, I wish to correct some of the
theories popularly current among the diggers,
according to which gold is to be traced to
the action of fire. The gold, in its original
position, is in larger or smaller particles
dispersed throughout the quartzose consti-
tuents of the mica and clay-slate formations.
By the gradual wearing away of these rocks,
through the action of the elements, extending
over immense periods of time, large masses
of debris have been formed, and nature itself
has executed an operation of goldwashing,
by collecting the heavier particles and
depositing them in the gullies of the streams,
or in the conglomerates covering the slopes
of the hills.

There are, therefore, two principal descrip-
tions of diggings: either "river diggings,"
in the beds of the streams, or "day diggings,"
in the conglomerate and gravel accumulated
by on the slopes of the mountains.

I will first describe the best known and
most worked of your gold-fields, namely,
the Aorere and Parapara gold-field.

The Aorere and Parapara Gold-field.

You are all aware that the gold in the Aorere
valley is confined to the eastern side of the
valley; the only traces of gold found on the
western side are on the Kaitune stream, but