THE ASHBURTON GOLD DISCOVERIES.
The following report on the Ashburton gold discoveries, has been forwarded
to the Colonial Secretary by the Government Geologist, Mr H. H. Page
Woodward: —
THE TOP CAMP.
Alluvial gold was first found on the Ashburton River, at the beginning of
this year, about 14 miles S of the tree marked 45 (triangle), in a creek
flowing down a gorge, about 200 feet deep, between steep cliffs of clay-
slate capped by almost horizontally bedded limestones.
These clay slates dip at a high angle to the N.E. They are intersected in
places by small quartz reefs or leaders, in many cases ferruginous, but up
to the present none of them have proved to be rich in gold. The capping
limestone (dolomite) and the underlying shaley, sandstone, and limestone
beds are probably a northern and eastern extension of the carboniferous
formation so largely developed on the Lyons and Gascoyne Rivers, there was
yet no fossils have been found by which their age can be definitely fixed.
The beds dip at an angle of 20 deg. S, resting unconformably upon the
upturned edges of the clay-slates, and along the line of junction many
strong springs arise. To the S these limestones form a large flat-topped
range or table land, and owing to their dip they completely cover the clay-
slates in this direction, even in the gullies and the stream beds, which
are here at a comparatively high elevation.
There cannot be the least doubt that the gold in the gullies has been
derived directly from the mineral veins in the clay-slates, for it has
never been found in those gullies where the slates are absent, and the
overlying formation is not of highly mineralized character. The mineral
veins must be of great antiquity as they must all have been formed prior
to the deposition of the superincumbent carboniferous rocks, for in no
case do they extend beyond the line of junction.
It is rather remarkable, that there are no conglomerate beds in this
district at the junction of these two formations; the limestone for the
most part resting directly upon the upturned edges of the clay slates.
Should any such conglomerates or detrital deposits be discovered, they
should be prospected, as it is highly probable they were proved rich in
gold.
The gold in this field is very pure, and free from quartz and ironstone.
All the larger pieces were of a flat bar shape, owing to their having been
formed between the slate ledges by the slow accumulation of fine gold,
which has been joined together by the gradual accretion of the minute
quantities held in solution by the water. The largest nugget weighed
about 6 lbs. It is estimated that from 9000 to 10,000 ozs. have been
taken from these diggings. The run of gold in the main gully extended for
over one mile in length, the most of the gullies N. and S. for a distance
of about 5 miles along this line have proved rich.
There is plenty of water on this field. Owing to other discoveries that
be made lower down the River, there are present only about 60 men working
here, who are all getting enough gold to pay their way, and most of them
must be doing pretty well, as they are nearly all old hands, who would not
stop and work for nothing. It is admitted that any one can get half an
ounce of fine gold a week anywhere, and that it would be considered a bad
week, unless, what is called, a "speck" weighing a few ounces were found.
Whence this gold is derived it is impossible to say without carefully
mapping and prospecting the area, but it is highly probable that it
results from slow accumulation from poor quartz and ironstone reefs,
though in some cases it may have been washed from older "leads" and
conglomerate beds, which, if they existed, must have followed the present
courses of the creeks, for no traces of such beds are now to be seen. The
deepest sinkings on this field are from two to three feet.
THE "SOLDIER'S SECRET" OR MIDDLE CAMP.
This field is situated about 20 miles N.W. of the former and about 14
miles up the Mount Blair Creek. It is very similar in formation to that
of the Top Camp, except that the flat topped limestone hills are two miles
to the S. The gullies run between steep clay slate hills and carry gold
for distances of 200 to 400 yards. The gold is much finer. It is
estimated that 1500 ounces have been found up to the present. The
diggings cover an area of about 5 square miles. Messrs. Cook & Green have
sunk a well in the bed of the Mount Blair Creek where there is a good
supply of water.
To the N.W. of the Camp there are the remains of an old lead crossing some
low hills, where fine gold occurs everywhere on the surface and in pockets
on a false bottom of travertine limestone. In the wash a great deal of
ironstone, some magnetic, is found with the gold, but, as at the Top Camp,
very little quartz.
Some large quartz reefs cross this line of country, forming high hills,
but it is not at all probable that they carry gold; the smaller reefs and
ferruginous veins are far more promising. The largest pieces of gold
found on this field weighed about an ounce, but larger may have been found
and not reported.
THE DEAD FINISH.
This field is situated on the north side of the river, about 5 miles north
of tree marked 35 with a triangle, and 6 north-west of Gregory's Deep
Creek. This patch of country is not nearly so hilly as the other fields,
and there is much more quartz, from which it is probable that the gold has
been derived, for it has been found in the gullies up to, but not higher
than, the quartz reefs. These diggings are the "stand-by" for any man who
is penniless, for he can be certain of enough gold to pay his way at these
workings. The gold is mostly nice and shotty, in character; a piece about
8 oz in weight has been found. It is estimated that about 1000 oz. has
been obtained. There are seventy men now at work. Unfortunately water
has to be carted about six miles, and the gold is not found so easily as
in some the other diggings [sic].
THE GORGE.
These diggings are situated a little to the south-west of the Dead Finish,
but on the other side of the river. Some nice nuggets were found, and a
rush set in, but the extent of country was neither large nor rich enough
for a number of men, so has been nearly deserted, but the few remaining
must be getting gold or they would not stop.
MOUNT MORTIMER DIGGINGS.
These diggings are situated about 7 miles S.E. of the hill marked on the
new maps as Mt Dawson, but which has always been known in the district as
Mt Mortimer.
The country here is slightly different from the upper fields, as the clay-
slates are often replaced by sandy slates and ferruginous sandstone beds,
and is generally harder, while the gullies are not so steep. The
"sinking" is, as a rule, deeper, and being so much harder a claim takes
longer to work out.
In one gully a quantity of large pieces of gold were found, the largest
weighing 56 ozs., but in the other gullies the gold, as a rule, is not
found in large pieces, and is generally associated with a good deal of
ironstone; indeed, the latter is often included, so that the lumps have to
be crushed in order to separate the gold. The nearest water is 5 miles
distant, but in spite of this there are about 200 men camped here, mostly
doing well, but as a claim takes a month or six weeks to work out, they
cannot make money so rapidly as a where they have only to rake out the
slate bars with a pick.
It is believed that about 2000 ozs. have already been sent away from this
field, as the claims are not yet half worked out, it will probably yield a
large quantity of gold.
GENERAL REMARKS.
An auriferous belt of country extends from Hick’s on the Ashburton ,
following this river in a S.E. direction for about 150 miles. It is
bounded on the S. by the Baxter Range and a flat-topped table land, which
follows the main course of the river at a distance of 14 miles to its S.
To the N. it extends across the Ashburton and Harding Rivers to Mount Wall
and De Courcey Range, i.e., a distance in a northerly direction from the
river of 20 to 30 miles, which gives an auriferous area of about 10,000
square miles.
The rocks are identical with those of the auriferous areas of the other
colonies, and entirely different from anything in this colony, to the
South of this district. The river follows the strike of their out-crop,
and their dip is mostly to the E. They consist of clay and chloritic
slates, sandstones and quartzites (the slates being often of the cleavable
kind used for roofing purposes), they are intersected by numerous quartz
and ferruginous lodes, which have often highly altered the slates in which
they occur, and these whitish and highly mineralized portions of the
country should be prospected. There is a most promising tract of this
class between the Dead Finish and Gregory's Deep Creek.
The general features a high slate ranges to the S., backed up in the
distance by flat-topped ranges. Large alluvial planes following the river
chiefly on the N. side, with here and there are low isolated slate hills
rising up through the plain, and some miles away to the N. slate ranges
again recur.
Up to the present very little prospecting has been done, as only the rich
patches in the shallow ground are considered worth troubling about, and as
there is no protection for the finder of a new field, the two or three
prospectors who have made such discoveries will not attempt to work them
till more men leave the field, as at the present time if one of the
prospectors lays in a large stock of rations, or is missed for a few days
he is at once tracked up by about 100 men, at which kind of work a large
number of men seem to spend their time.
In the large planes of the Ashburton there are sure to be some very rich
deposits of gold found, but as the prospecting will be most expensive
work, no man will undertake it, unless he be granted a protection area,
until the course of the leads has been ascertained.
Taken as a whole this is a most promising tract of country and will,
without doubt, prove a rich and lasting goldfield, but it is highly
probable that before this is proved that everyone may leave the field
under the impression that all gold is worked out, when they have scratched
all they can from the slate bars of the small gullies in the ranges, but
there will still remain that which will yield the best returns, viz: the
deep ground as yet untouched.
This field, as far as it has been worked, has been the most productive in
the colony, for about 15,000 ounces have been raised since January, and it
is only during the last three months that many men (600) have been on the
ground.
