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about 3000 diggers took place, and about 1000 ozs, gold were obtained but the whole enterprise collapsed in about six months; the field was thought to be too poor to pay and was abandoned. Prospecting however continued, and in 1856, gold was found by Mr. Ligar in Mataura River, and by Mr. J.T. Thompson at several places in Otago. In 1861 Mr. Gabriel Reed discovered gold in a gully (since become famous as Gabriel's Gully), leading into the Tuapeka River. The results he obtained were so satisfactory, that a great rush took place, and other valuable discoveries rapidly succeeding, a state of the wildest excitement followed, and gold mining became established as one of the most important industries of New Zealand.
Occurrence.-Gold commonly occurs in the metallic form, never pure, but always alloyed to a greater or less extent with silver. It is also frequently contained in Iron Pyrites, but in what state of combination, or otherwise, is not satisfactorily determined. There are three conditions under which gold is found, 1. Shallow placer or surface alluvial deposits, the beds of present or recent rivers and streams, and sea coasts, 2. Deep placers, or leads, which are cements, or consolidated gravels resulting from the denudation of the rocks containing the gold bearing veins, and are often the beds of ancient glacial rivers. The shallow placers frequently result from the washing, concentration, and reassorting of the old deep placer deposits, by a modern system of drainage differing from the ancient. In alluvial deposits the gold is in the form of scales or flattened grains, and is usually fine, large nuggets being very rare, the largest yet reported is one of 53 ozs found in a creek near Lyell in 1878. 3. Veins or reefs, which are the original depositories of the precious metal, chiefly found in the ancient slates of Silurian, Devonian, or older Carboniferous age, where these have undergone extensive metamorphism, or in the associated volcanic rocks. The gangue is usually quartz and the gold is found in irregular plates and disseminated in small grains, often invisible to the unaided eye. Occasionally filaments or small branch-like forms occur which close examination shews to be built up of minute octahedra. The minerals commonly asso
ciated with gold in the reefs are the sulphides of iron, copper, lead, zinc, and antimony, and it is noted that lodes carrying much iron pyrites are often the most permanent in yield, and the widest reefs are seldom
rich. Methods of Mining.—In the early days alluvial gold was separated from the sands and clay of the river beds by washing in a "pan", a shallow wood or tin dish, its great specific gravity rendering this a simple matter. This was succeeded by a variety of cradles, toms, &c., but all these are now almost entirely superseded by the “ sluice” which is simply a trough or channel through which a stream of water flows, and into which the earth or “pay dirt” is thrown. The force of the current breaks this up and liberates the particles of gold which are arrested by “ riffles” or stops placed at intervals across the trough, while the lighter earth is carried away to increase the
spoil” at the foot of the tail race. Mercury is often dropped in at the head of the sluice which as it trickles down the trough picks up the light grains of gold and forms an amalgam which lodges against the rifles. After running a certain time the feed of water is stopped, and the gold and amalgam collected, retorted to recover the quicksilver, and melted. Hydraulicing is the same in principle as sluicing, the face of the deposit being attacked by powerful jets of water, which break it down and carry it into the head of the sluices. Reef quartz and hard cements are first crushed very fine in stamping mills to liberate the gold, after which they are treated by water and mercury on the same principles as the sluices. There are of course many modifications and variations in the precise methods adopted under differing circumstances, and the treatment of auriferous pyrites is a somewhat difficult and complicated matter, which we cannot stop to consider. The foregoing outline of the general principles, will, it is hoped suffice to render the following notes intelligible.
Distribution.--Gold is very widely distributed over the South Island, but in the North Island it has only so far been found in payable quantities in the part of Auckland lying east of the Thames River and Gulf, extending from Coromandel Harbour on the North to Te Aroha on the South about 70 miles with a breadth of 16 to 25 miles. This is the oldest gold field in New Zealand having been proclaimed in 1854, and is divided into three districts, North and South Hauraki, and Te Aroha.
North Hauraki or Coromandel. The Coromandel peninsula is a rocky mountain ridge, traversed by deep precipitous ravines or creeks, and covered by dense timber. The basement rock consists of ancient slates, resting on which are massive igneous tufas, varying in structure from a compact greenstone trachyte or propylite to a coarse breccia of angular fragments embedded in a tufaceous cement. They are possibly of cretaceous age, contain quartz reefs, and at Coromandel are overlaid by brown coal beds, on which are Volcanic rocks of probably Eocene age. The beds of the Tufa formation are decomposed in a very irregular manner, the unaltered rocks rising to the surface in ridges ; and they are usually pyritous. The quartz reefs vary greatly in thickness and where they pass through the soft decomposed beds are usually auriferous, but in the hard undecomposed beds they are sometimes pinched out or become very poor. The associated minerals are blende, galena, manganese, silver, iron and copper pyrites, antimony and occasionally arsenic. "The gold is extremely patchy sometimes very finely disseminated, often aggregated, specimens being found which are nearly half gold. The greatest depth to which the reefs have been proved in this district is at the Kapanga Mine 450 feet where the reef is 2 ft. to 4 ft. wide and auriferous. Very rich reefs have recently been found at Tiki, and at Matawai, where 1 cwt. of stone taken from a reef 4 ft. to 5 ft. wide yielded oz. of gold to the pound of stone. The average yield of the district in 1881 was 6 oz. 17 dwts. to the ton of quartz.
The South Hauraki, or Thames District, is at the head of the Thames Gulf, near Shortland and Grahamstown. general character the country and the reefs much resemble those more to the north. Some of the most successful of the mines are here situated, the dividends realised having been
enormous. For instance, the fortunate shareholders in the Golden Crown, realised £200,000 in one year, and the Caledonian £572,000 in a like period. The Moanatairi in one month yielded 22,555 ozs. gold, the produce for 18 days being 11,148 ozs., of a value of £29,000, all of which came from a block of ten feet square and three feet thick. Water has been a great obstacle in this district, and a large jointly-owned pump has been erected to cope with it. There has, however, been less harmony amongst the contributing companies than their evident mutual self-interest might have been expected to produce, and the pump has repeatedly had to stop for want of funds, resulting in the flooding of the mines. The greatest depth attained is at the Queen of Beauty, nearly 600 feet, at which depth excellent returns were being got when the stoppage of the big pump caused the flooding out of the mine. The Caledonian reef varies from 9 inches to 20 feet in thick
In the year ending March, 1881, the average yield of this district was 1 oz. 12 dwts. per ton of quartz crushed.
Te Aroha district, in 1881, caused some stir, owing to the discovery of an immense quartz reef, which, at an elevation of nearly 2000 feet, is exposed on the east side of the range. The soft wall has worn away and left the reef exposed, towering up above the tops of the trees in some places, to a height of 100 to 300 feet a wall of quartz 20 feet thick. Five feet of this shews gold in black veins, permeating the stone; the yield being about 2 oz. to a ton. Several other reefs are found adjoining, varying from 2 feet to 4 feet thick, and the existence of payable gold has been ascertained over an extent of one mile along the line of the main reef, and a quarter of a mile on each side.
Hawke's Bay.--The existence of gold-bearing reefs near Mohaka has recently been ascertained.
Wellington.--Reefs are found in the Wairarapa district, in a series of soft black slates, but the yield has not hitherto been satisfactory. Near Cape Terawhiti, in a rubbly sandstone, there are reefs, specimens from which have yielded from 7 dwts. to 3 oz. 17 dwts to the ton, and as the district
is being vigorously prospected, possibly it may become important. The Rimutaka and Tararua ranges hold well defined auriferous reefs, but none have yet yielded gold in paying quantities.
Marlborough. - The gold fields in this province are nivided into three districts.
Pelorous, on the Wakamarina River, about 15 miles from Havelock, where alluvial gold was found in 1864, and a rush took place ; but the easier got gold was soon exhausted, and the place is now almost deserted, only a little sluicing going on, with not very profitable results.
Blenheim or Wairau River is also alluvial, and worked with but mediocre results. In the dividing range between these two rivers gold-bearing quartz reefs are known to exist, and recently one is reported at Dead Horse Creek, 10 to 12 feet thick, of payable quality. The Sutherland reef was
. worked for a short time, and contained sugary quartz, yielding from 1 grain to 1 oz. per ton.
Queen (harlotte Sound.— Near Picton, some quartz leaders in mica schist and clay slate, yielded 3 to 14 ozs. per ton ; and near Cape Jackson, some well-defined reefs in foliated micaceous schists and blue slates are being worked by the Ravenscliffe and Golden Eagle Companies, with extremely poor results; the latter, in 1881, crushed 20 tons for 10 ozs. gold.
Nelson.—It has already been mentioned that the first discovery of gold in New Zealand was made by Captain Wakefield, in this province. The field is divided into the following districts.
Wangapeka River, where the gold is all alluvial, and almost exhausted. In 1869, auriferous reefs were found in altered pyritous slate, but are not worked.
Collingwood and Takaka.-In 1856, alluvial gold was found in the Aorere river, which led to a rush, and some rich finds were made, especially in Slate River, and in Bedstead Gully, and other tributaries. The gold is widely disseminated, and only here and there occurs in payable quantities, on the