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The Pamphlet Collection of Sir Robert Stout: Volume 70

A.—Minerals which have been worked in the Colony

A.—Minerals which have been worked in the Colony.

(1) Antimony.

Antimony occurs widely distributed throughout the colony, from the Bay of Islands, in Auckland, to the south of Otago. In many places it is auriferous, and is worked as part of the reef, but very frequently, after extracting as much gold as can be done by crushing and amalgamation, the stibnite is allowed to flow away with the tailings. Many efforts have been made to work it, and notwithstanding several somewhat conspicuous failures the industry bids fair to become well established.

In Auckland Province antimony occurs, as already mentioned, at the Bay of Islands, and also at the Thames, Waiatohi Creek, and Coromandel.

It is, however, in Queen Charlotte Sound, Marlborough Province, that the largest deposit of stibnite has been found, and in this locality an effort has been made to work on a large scale. The discovery was made in 1873, and the analysis gave 51.12 to 69.4 per cent of antimony. At this place the country is a fine-grained, greenish, schistose rock, changing in parts to a greyer colour, and becoming more quartzose. The lodes, of which there are three, vary a good deal in thickness and quality, and contain an appreciable amount of gold. The main reef has been followed from the north-eastern corner of the lease in a northwesterly direction for about 140 chains, and in the opposite course it may be traced on the same line of strike for about 4 miles. Its structure is peculiar, in that the stibnite forms the lode, and the quartzose part is disseminated through the ore. With the antimony are found loose blocks of olivine, with chromium ore, compact hornblende rock, and white and green chert.

A small company of Wellington (New Zealand) capitalists expended £25,000 in plant and works, including a dressing plant and smelting furnaces, but the undertaking proved to be unremunerative, and the property passed into the hands of an English company who worked on a much larger scale but with no better result. The ore appears to have been plentiful, bat as is usual in such deposits was bunchy and a good deal faulted.

The dressing plant consisted, in 1890, of one Blake rock-breaker, one Marsden ore-crusher, one Lucop centrifugal pulverizer, and various page 41 other appliances. The use of the Lucop pulverizer had been discontinued, but the Marsden crasher gave great satisfaction. Still the general result of the concentrating plant appears to have been very unsatisfactory, and the first smelting-works which were erected were so inefficient that they were dismantled. During 1890, 515 tons of ore, containing from 48 to 60 per cent, of antimony, with a value of £11,121, was exported by this company, but according to the Otago Witness of March 31th, 1892, the mine was put up to auction in that month, and no bid was obtained. Advices dated June 9th, 1892, stated that a syndicate had purchased the mine, and decided to go on with the work.

Passing by Collingwood, where a complex antimoniferous ore occurs, which will be described under another heading, the next deposit is at Reefton, in Nelson Province, where stibnite occurs plentifully as a constituent of the gold-bearing reef a, and also near Black's Point where, at a distance of about 1½ miles from the lnangahua River, and at an altitude of about 800 feet above the stream, or 1,400 feet above the sea-level, a number of blocks occur, which have received some attention. The surface of the country is densely clad with forest and undergrowth, and consequently prospecting has been carried on under difficulties.

About 3 miles from Brunnerton, on the Greymouth-Reefton Railway, and 8 from Greymouth, quartz reefs had been known for many years, but had not attracted much attention until about the year 1878, when blocks of richly auriferous stibnite were found in the alluvium. The quartz reefs are about 600 feet above the river, and at 400 feet higher the lode from which the specimens were derived was discovered. It is about 9 feet in thickness, is included in hard blue cherty slate, and consists of five distinct bands, as follows:—
Ft. Ins.
No. 1, next the footwall, is quartz containing stibnite dispersed in irregular masses 2 0
No. 2, compact stibnite 2 0
No. 3, stibnite, including quartz in the form of nodules 3 0
No. 4, fine-grained mixture of quarts and stibnite 0 4
No. 5, breccia of slate 1 8
9 0

The first specimens forwarded gave the astounding result of 84 ounces of gold and 86 ounces of silver per ton, or an assay value of £830. Subsequent specimens obtained by Sir James Hector did not give anything like such a good yield, the highest being from No. 2, which assayed 32 ounces of gold to the ton. Still, the prospects were exceedingly alluring, and if the reef had maintained its thickness, the results would page 42 no doubt have been satisfactory. This was not, however, the case, and the mine was abandoned without any very decisive test of the property being made.

Other localities on the west coast, where antimony is found, are Westport, Blackball Creek, near Greymouth, and Hokitika.

In Otago, ores of this nature occur, and are now being worked, as for instance at Hindon, where a 7 feet lode occurs about 1,000 feet above the river, and has yielded 500 tons (worth £10 to £20 in London). The reefs in this locality were known in 1864, but for many years remained unworked. Recently an energetic private firm has taken up the lease, and as the lode is well-defined, and the mine within easy distance of the recently opened Otago Central Railway, the prospects should be good.

At Stony Creek, near Waipori, Otago, the antimony deposits at one time offered considerable inducement for investors, and in 1875, 60 tons of ore was sent to England to be smelted. The lode, which is composed partly of fibrous and partly of compact stibnite, is 2 feet 6 inches in thickness, and has been traced for several hundred feet. Scarcity of fuel and timber constitutes a considerable drawback to cheap working, and but little has been done.

On the Carrick Range, near Cromwell, Otago, outcrops which have been traced for upwards of a mile occur at an altitude of 3,000 feet above the sea. The reefs traverse grey foliated mica-schists, and are stated to be thin. But little has been done in this locality.

In addition to the places already named, antimony occurs widely distributed throughout the colony, as for instance in the Provinces of napier and Wellington, and at Dunedin, in Otago, and with such quantities undoubtedly existing, the fact of so little being worked seems remarkable. One reason lies in the superior attractions of gold, and the fact that, although comparatively easy to treat, antimony ores require special knowledge and also fuel, which is often absent in the locality of the find.

The export of the ore commenced in 1878, with 4 tons, valued at £102, and reached, in 1800, 515 tons, valued at £11,121; altogether £36,190 worth has been sent out of the colony. In the year 1883 a bonus of £500 was offered for the first 250 tons of antimony regulus produced in New Zealand, and sold at a fair price in a foreign market; but no application was made, and consequently the reward lapsed.

(2) Copper.

Copper has been known in New Zealand since 1842, when a lode of chalcopyrite, or copper pyrites, was worked on the island of Kawau, page 43 Auckland Province, It occurs elsewhere in various forms, as native metal in the Nelson serpentine belt; near Lake Wakatipuin, Otago; at the Great Barrier Island, in Auckland; in the Perseverance Mine, Collingwood; at Maharahara, near Woodville, North Island; and in small quantities distributed in basaltic dykes traversing trachy-dolerite breccias, near the Manukau Heads, Auckland.

In addition the following ores are found:—Cuprite or red copper ore, occurs in the serpentine belt of Nelson, where it is found yielding from 10 per cent. to 88.9 per cent. It is also found at Bligh Sound, in Otago; at Tokomairiro, Otago; and at the Thames. With it is frequently associated copper glance, or chalcocita. Chalcopyrite, or copper pyrites, which has already been mentioned as having been found at Kawau, was worked for several years, with a yield of metal at first of 16 per cent., then of 8 per cent., and finally, at the deepest point, of 5 per cent. When the mine was abandoned, principally on account of the high price of coal, consequent on the recent gold discoveries, the lode was said to be 15 feet thick. The same ore has again been worked at the Great Barrier Island, Auckland, in conjunction with peacock ore, malachite, azurite, and mela-conite. At Moke Creek, near Lake Wakatipu, Otago, a lode 4 feet wide is found, consisting of 5 inches to 8 inches of chalcopyrite, and 3 feet 8 inches of gangue, with a little metallic copper scattered through it. Another locality is the Paringa River, Westland, and specimens have been obtained from the Thames, where it is associated with gold; from the Moorhouse Range (Canterbury), near Mount Cook; at Dusky Sound, on the west coast of Otago; and at Lake Okou.

The neighbourhood of Nelson has been the site of some of the most recent attempts to produce copper, and the Champion Company, though not now in operation, erected works on a scale of considerable magnitude, The lodes seem to be of the nature of contact deposits, and occur where the red and green Maitai slates, of Lower Carboniferous age, abut on massive beds of diorite and greenstone, changing on the east into compact serpentine, with large intrusive masses of the olivine rock charged with chrome iron, and known (from the Dun Mountain) as dunite.

There are in the Champion property three lodes, known respectively as the Champion, the United, and the Maitai. The first-named consists, so far as is known, of a vein of rather soft serpentine, about 4 feet thick, between walls of compact serpentine, and contains, near the hanging wall, irregular lumps of metallic copper, with various adhering sulphides and oxides. Towards the footwall are masses of magnetite and pyrrhotine, and in some portions of the lode kernels of yellow sulphide and copper page 44 glance (grey sulphide). In the United lode metallic copper does not occur, and the body of the lode is almost entirely composed of yellow sulphide. In the Maitai lode, which has not been much explored, the ore is mostly grey sulphide.

A large amount of dead-work was carried out, expensive roads were constructed, reducing works, with elaborate appliances, and laboratories were built, and everything laid out for complete copper mining and smelting. In all, the expenditure was about £34,000, and the average yield of all the ore produced, including native metal, was 7½ per cent., but owing to the decrease in the value of copper, the undertaking failed to pay. The estimated cost of producing fine copper was £28 to £29 per ton.

The Nelson mineral belt which has been alluded to extends from the Dun Mountain to D'Urville Island, and is covered by the Maitai series, which consists of green and purple slates (highly cleaved) and then calcareous slates, traversed by veins of calcspar, and passing eventually into a regular bed of limestone, beyond which the slates (still calcareous in character) again come in, and are succeeded by the serpentine which may be traced from the Dun Mountain to the Croixelles, reappearing at D'Urville Island. At this last-named locality an attempt to mine was made in 1878 and 1879, the deposit consisting of a true but patchy lode of copper glance. The average return from 50 tons shipped to Melbourne was 10 per cent., but the ore was imperfectly picked.

In the early fifties an English company expended large sums of money in an attempt to work the Dun Mountain copper deposits, near Nelson, The mine was 2,500 feet above the sea, and was connected with the port by a railway, 12½ miles long, with a gradient (for a large proportion of the distance) of 1 in 18, This and other extravagances, which were committed before sufficient ore was proved, caused failure. The company expired, and for many years the property lay idle. Of late years, however, an attempt has been made to re-start it, and evidence has been obtained that the original company did not pay so much attention to the indications of the lodes as would have been prudent. While these were being followed, rich deposits of chrome ore were met with, and money, which should have gone towards proving the copper-bearing lodes, was diverted, When the price of chrome fell the available capital had been expended, and operations ceased.

Near Nelson, in the Aniseed Valley, is an interesting occurrence of native copper, interspersed in minute grains through a matrix of granular serpentine. On analysis it was found to contain from 2 per cent, to 6 per page 45 cent. of copper. A similar deposit has been found in the Serpentine Valley, lying to the south-west of the above locality, but in neither case has much been done towards proving the continuity of the bed. In the same valley redruthite or copper glance, cuprite or red oxide, and native copper occur in bunches at the Aniseed Valley Mine, but no well-defined lode is known, and at the Red Hill Mine, near Collingwood, a dark ore with resinous lustre has been found, which proved to be an intimate mixture of zinc blende, chalcopyrite, and galena.

So long ago as 1870, a discovery was made on a claim in Bedstead Gully, Collingwood, of fine specimens of chalcopyrite, and though the prospects were at the time considered to be excellent, nothing has since been done.

In Wellington Province, copper is noted as occurring at Porirua, and at Maharahara, near Woodville, and has been for some years worked. The deposit, which was first found on the slope of the Ruahine Range by Mr. Price, and consists of the native metal with various ores, is associated with red cherty rocks and h æmatite. The writer is unaware of the precise nature of the company's operations, but the March, 1892, newspapers stated that rich ore was at that time being mined.

The west coast of the South Island contains several deposits of the metal under consideration. On the Buller River, copper was found in 1874, and on the Paparoa Range in 1886; also at the Haast River a deposit is known 2 feet in thickness, and yielding 85 per cent, of copper; this is on the face of the Okura-Matakitaki Range, and within 6 miles of coal outcrops; and it is known to occur at Paringa, None of these, however have been worked, but at Dusky Sound, in the south, mining operations have been carried on. The lode here, which is 5 feet thick, consists of chalcopyrite, with pyrrhotine and magnetic iron pyrites, and yielded from 23.5 per cent. to mere traces. The associated rock is hornblende-gneiss, which varies from hornblende-rock to felspathic-gueiss, and is traversed by veins of granite. The site is only about half a mile from the shore, where there is good anchorage, but the explorations so far have gone to prove the non-existence of any well-defined lode.

In the Province of Canterbury there are, with the exception of a deposit in the Moorhouse Range, near Mount Cook, no copper ores, but in Otago—besides those occurring on the west coast, and already mentioned—are several deposits, some of which have been worked to a small extent.

About 1865, £2,000 was expended near Waipori, Otago, in a futile effort to discover a well-defined lode, and in 1862, pyritous ore containing page 46 24 per cent. of copper was found near Ben Lomond, between Late Wakatipu and Moke Creek, This is a true lode 1½ feet thick, dipping at an angle of 15 degs. Specimens have been found at Tokomairiro, and on the Car rick Range, near Cromwell.

It will have been observed that copper ores and the native metal are widely distributed in New Zealand, at several places in Auckland, in Wellington, through the Nelson mineral belt, at Collingwood, scattered through the west coast of the South Island, in Canterbury sparingly, and in Otago at various places. Also that the yield varies from pure metal downwards. In hardly any of these places has the working been earned out with any degree of perseverance, and in many cases, no doubt, what energy has been expended was misdirected, and the difficulties attendant upon copper smelting have militated against the success of the industry. Possibly, in future years, more skilled and determined efforts will be made.

The export of copper ore has been exceedingly variable. It commenced in 1858 with 351 tons, valued at £5,000, and has never again reached anything like the same figure. For several years, as will be seen on reference to the table (see Appendix), little or none has been exported.

(3) Manganese.

Manganese ores have been exported uninterruptedly since the year 1878, when 2,516 tons, valued at £10,416, was the yield, but in only one succeeding year has the original figure been equalled, and the supply shows a falling off. The total quantity is 15,803 tons valued at £51,291 During 1890, the Colonial Manganese Company produced from Waiheke Island, Auckland, 1,020 tons, valued at £2 per ton, while 150 tons valued at £2 5s. per ton came from Whangarei. Pyrolusite occurs sparingly in the colony, having been discovered in Auckland in 1873, and the only other locality known is in the same province, where the mineral was found in 1878. Hausmannite and braunite have also been noted. Manganite, psilomelane, and wad, all hydrous ores, are very plentiful; manganite in Otago, in the alluvial drift of the Kawarau and Clutha Rivers, and also an apparently extensive deposit near Taieri Mouth. An attempt was made, in 1890, to work the ore in the last-mentioned locality. In Auckland it is found at Tararu Creek (Thames), at Kawakawa, on the island of Waiheke, and at Whangarei. Tory Channel (Marlborough) and Wellington are other known localities. Wad occurs in most of the places already mentioned, and in addition to the above commercially valuable ores are found diallogite (carbonate of manganese), rhodonite (silicate), and mangano-calcite.

page 47

(4) Tin.

This exceedingly valuable metal has not yet been commercially worked in New Zealand. For some years the existence of tin ore in many localities had been known; for instance, in the auriferous conglomerates at the base of the Coal-measures at Lankey's Creek, Reefton, at Milford and Dusky Sounds on the west coast of Otago. A discovery was reported near Waikouaiti, Otago, in 1886, and undoubted cassiterite was brought down; but on investigation by the writer there appeared to be not the slightest indication of stanniferous rocks, and the "hardy prospector" failed to point out the locality of the supposed find. In the latter part of 1888, a discovery of tin ore took place in Stewart Island, where wash containing stream tin was found on the lower ground, and in the Remarkable Mountains cassiterite in situ associated with gneissic granitoid rocks. In a very few months an area of 8,280 acres had been applied for, mostly "wild-eat" claims, without a possibility of success. Of this area, 7,000 acres were taken up. By the early part of 1890, the shadow of failure had come over most of these speculations, and the intense excitement had to a great extent abated and given way to bitter regrets, The rosy prospects had faded, the rich alluvial deposits of stream tin had been proved to exist mostly in the imagination of promoters, and what little work had been done at the reefs only proved them to be unstable. The climate is excessively wet, the ground on low levels covered with an almost impenetrable scrub, and even if rich alluvial deposits existed, there is not a sufficient supply of water to afford employment to a large population. At present, the writer believes, the field is practically deserted.

Quite recently (April, 1802) stream tin has been found among the gold wash at Humphrey's Galley, near Hokitika, on the west coast of the South Island.

(5) Scheelite.

Scheelite, or tungstate of lime, is remarkable for its high specific gravity (5.9 to 6.076), and for this reason attracted the notice of the early diggers. It was discovered in Otago prior to 1865 in the Buckle Burn, Rees River, also at Wakatipu Lake and Waipori, and was determined by Dr. Hector. Mr. McKay subsequently found it in silu on the west side of the Richardson Mountains in a reef 4 feet wide with mispickel, and its occurrence at Reefton, Wakamarina Valley, and Havelock (Marlborough) is on record, as well as at Macraes, near Palmerston (Otago), whence a second shipment has just been sent to England, In reply to enquiries recently addressed to the Colonial Government by the page 48 Consul-General for Portugal, at Hanover, Prof. Ulrich, F.G.S., has reported that the demand is so intermittent that it does not pay to keep the mines at Lake Wakatipu open. Unfortunately no details of its export can be given as it is included in the published returns with other minerals, It is probable that ample supplies exist in the colony.

(6) Chromium Ores.

Chromite, or chromic iron, occurs plentifully in the mineral belt of the Nelson district, also at Jackson's Bay, in the Lake Harris Range, at Milford Sound, where a large block of nephrite was found sprinkled with it, and at Moke Creek, Otago. It is found where olivine rocks occur, and in Nelson as a constituent of the peculiarly hard variety of serpentine known as dunite, sometimes forming more than 50 per cent, of the mass. The ore is very rich, averaging over 55 per cent. of chromium oxide. In the Dun Mountain Copper Mining Company's lease a 10 feet band of the ore occurs, and one in the Roding River Company's ground measures over 15 feet in width, and has been proved vertically for 300 or 400 feet.

At one time the yield of chromium oxide was of considerable importance to the colony, the maximum having been reached in 1862 when 3,843 tons valued at £24,719 was exported. Almost immediately after that the industry became extinct, and 1860 was the last year of its existence, so far as export was concerned.*

Altogether 5,666 tons, valued at £37tS67, has been exported, and it is probable that when the demand increases or the nearer supplies have become exhausted that the undoubtedly large deposits existing in New Zealand will become of value.

* On reference to the Geological Survey Reports, 1881, page 7, this information, which derived from the Mines Department Report appears to be hardly correct.

(7) Silver.

As has already been stated, the gold found in the Auckland district is alloyed to a considerable extent with silver, the latter sometimes forming 30 per cent, of the mass, and it is from this source that the bulk of this metal exported from the colony has been derived.

Quite recently a silver-mining field has been opened up at Puhipuhi, about 22 miles from Whangarei and 16 miles from Kawakawa, in the Province of Auckland, The discovery was made by gum-diggers in October, 1888; the field was proclaimed in March, 1890, and was immediately "rushed;" but, as is frequently the case, a reaction seems to have set in, partly, no doubt, on account of the exceedingly bad roads. The reefs are of varying thickness, from 7 feet downwards, and the page 49 ores found comprise argentite or silver glance, pyrargyrite or ruby silver, and small grains of the native metal. Gold is found in small quantities. Mr. Alex. McKay, F.G.S., has recently visited the Puhipuhi district, and according to the Colonial papers of Jane 9th, 1892, considers that the field forms part of a mineralized district extending along the eastern coast of Auckland peninsula both north and south. The reefs, he states, are well defined, and prove that they live to a vertical distance of 500 to 700 feet. Almost all the leads contain silver ore, though at present the average yield is not sufficient to enable it to be treated profitably; but Mr. McKay's opinion is that the district is a legitimate field for mining enterprise.

A number of assays made from a lease known as the Prospectors' Ground gave from 200 ounces to 10 ounces per ton, and specimens from No. 8 reef as high as 2,000 ounces, while the average of nine assays was 128 ounces. The plant on the ground consisted in 1890 of a stonebreaker, one pair of Cornish rolls, a pulverizer, four amalgamating-pans, etc.

From the time the field was open, to the commencement of 1891, twenty claims had been taken up, and a small amount of work done; but, so far as the writer is aware, the bulk of the operations seem to have been purely of a prospecting nature.

A remarkably interesting and apparently valuable deposit of silver ore occurs near Collingwood (Nelson), on the Parapara River. The lode was discovered by Mr. Washbourne, and the character of the stone was determined in the Colonial Laboratory, where it had been sent for analysis as an iron ore. The containing rock is gneissic schist, passing into steatite, and farther to the west are slates and fine ciystalline marble; the lode when first discovered was about 24 inches wide, and yielded from 21 ounces to 1,792 ounces of silver per ton. It subsequently increased to 5 feet in width, but the yield went down to from 22 ounces to 51 ounces per ton. At the bottom of the shaft a return of 85 ounces to 110 ounces was obtained.

The lode was sunk on for 56 feet, and driven on for 36 feet, and from the end of this drive, where the ore had changed to an argentiferous galena, 5 tons was got, which averaged 40 ounces of silver to the ton, and 3 cwts. yielding at the rate of 300 ounces. The lode in this part then became barren, and work was stopped for fear of letting in the water from the river. Other works were then carried out, which succeeded in proving that the lode was well-defined, extended over a considerable area, and was of variable thickness and richness. The ore, which has been named Richmondite, from the locality where it occurs, is a variety of tetrahedrite, and gave the following percentage composition:— page 50
Per Cent.
Sulphide of lead 36.12
Sulphide antimony 22.20
Sulphide bismuth traces.
Sulphide copper 19.31
Sulphide iron 13.59
Sulphide zinc 5.87
Sulphide silver 2.39
Sulphide manganese .52

The mine has not been worked for some years.

In 1889, geocronite or antimonide and sulphide of lead, yielding 125 ounces of silver to the ton, was brought from Collingwood. Another deposit of silver ore, occurring at Mount Rangitoto, 20 miles south of Hokitika, merits a passing notice, On the southern face of this mountain is a lode 10 inches thick, consisting of pyrites, with about 20 per cent, of galena. A specimen brought by Mr. Cox assayed 10 ounces 17 dwts. of silver per ton; but samples tried in the Melbourne University Laboratory gave a yield of 735 ounces. The highest obtained by Mr. Skey, the able chemist attached to the New Zealand Colonial Laboratory, was 10 ounces 17 dwts.; but it must be remembered that the Melbourne University results were given on the galena, and not on the ore.

As the workings were continued the lode changed to a vein of solid pyrites, with a very little galena scattered through it.

During 1890, the amount of silver exported was 32,637 ounces, valued at £6,162, whereas in 1871 it was 80,272 ounces, valued at £23,145. Altogether since the commencement in 1869, 554,610 ounces, valued at £134,997, have been exported.

(8) Iron.

Ores.—The ores of iron occurring in New Zealand are both numerous and abundant, and have been divided by Sir James Hector into (1) granular, and (2) massive.

The first-named variety, that is ironsand, is very widely distributed in the colony, but the littoral deposits of the west coasts of both islands are the most remarkable; and at Taranaki the shore-line between high and low water-marks is, for great distances, composed almost entirely of this material. At the Manukau Heads also a similar formation occurs. The iron contained in this sand is present in the form of magnetite, h æmatite, or as titaniferous oxide. The magnetite is derived principally from acidic rocks, such as the granites of the South Island and the trachytes of the North; while the h æ matites or specular ores are derived from the page 51 metamorphic schists, and the titanic oxides from the diorites and basaltic rocks.

The analyses of ironsand which have been made, give from 70 per cent. of iron; and it is a noteworthy fact that most of the sands from the South Island are auriferous.

The following massive ores have been examined:—
(a)Magnetite (impure) from Manukau, Auckland. This is merely black sand cemented by oxidation, and is tolerably abundant. It contains 60.2 per cent, of magnetite, 37'9 per cent. of h æmatite, and 1-9 per cent. of siliceous matter.
(b)Gives 86'32 per cent of magnetite, and 13.68 per cent, of siliceous matter-It occurs in chlorite schists, in a very inaccessible part of the interior of Otago. The rock is a very compact foliated diorite, with crystals of magnetite,
(c)Yields 96.11 per cent, of magnetite, and 3.89 percent, siliceous matter. It occurs in mica-schist in the vicinity of Lake Wakatipu, Otago, near deposits of limestone.
(d)Is found in the serpentine series of the Nelson mineral belt, on the lease formerly belonging to the Dun Mountain Copper Company. The analysis is 90.6 per cent, of h æmatite, and 7.6 per cent, of siliceous matter. The thickness of the lode, which occurs with red, grey, and blue oxides of copper, and is auriferous, was not proved.
(e)Is from Maramarna, Auckland Province, and contains hæmatite and magnetite, with raanganeae5 but its percentage of silica is high.
The next four samples belong to the hydrous ores, of which—
(a)Is a bog ore, somewhat inferior in quality, as it contains much sulphur, 13.2 per cent, of water, and 13.83 per cent, of siliceous impurities.
(b)Is a brown ore, from the Tertiary coal-formation of Raglan, near Auckland, and is found in the form of balls or concretionary masses in the coal shales. The following is a detailed analysis:—
Per Cent.
Sesquixide of iron 72.69
Oxide of manganese .56
Alumina 1.16
Lime .27
Magnesia .69
Phosphoric acid .70
Sulphide of iron traces.
Siliceous matter 6.30
Water hygroscopic 4.61
Water constitutional 13.02
page 52
(c)Is a sample of the great Parapara limonitic deposit, which occurs in enormous quantities on the surface of the ground near Collingwood, Nelson, It is the hydrated ferric oxide, having the formula 2 Fe2O3, H2O, and contains when pure 59.89 per cent, of iron, At this place it is found massive, earthy, botryoidal, mammillary, and concretionary, and covers the earth in large dark brown masses, sometimes of many tons in weight. On breaking these lumps there is frequently disclosed a kernel of undecomposed sulphide of iron; and Mr. Cox's opinion is that the deposit is the oxidized cap of a large pyritous lode. The writer has traced this deposit for 2,772 yards within the original lease, and is of opinion that it extends to the Onakaka Creek, a further distance of more than a mile. Interspersed among it are waterworn quartz-pebbles, which would necessitate hand-picking. A sample gave:—
Per Cent.
Sesquioxide of iron 62.68
Manganese traces.
Lime .61
Magnesia traces.
Siliceous matter 23.47
Water 13.24
And a sample of iron made from it at Melbourne, in 1873, showed the following percentage composition:—
Per Cent.
Iron 97.668
Manganese .268
Carbon, combined .542
Carbon, free (graphite) .208
Silicon, with titanium, traces 1.004
Phosphorus .041
Sulphur .269

The situation is admirably adapted for the site of an iron-smelting plant. Close to the limonite is a deposit of nearly pure crystalline marble, and 5 miles away is the Collingwood coal-mine, yielding some of the best fuel in the colony. Facilities exist for the formation of a well-sheltered deep-water wharf.

Another deposit of a similar nature has been found at Mount Peel, Nelson.

page 53
At the Collingwood coal-mine in the Upper Secondary coal-formation occur deposits of spathic ore, of which the following analyses may be given:—
1 Per Cent. 2 Per Cent.
Peroxide of iron 35.23 40.38
Sesquioxide of iron 25.77 5.26
Oxide of manganese 1.10 traces.
Alumina 2.11 .40
Magnesia 1.91 .63
Silica .90 .55
Phosphoric acid not determined. not determined.
Sulphuric acid traces. traces.
Carbonic acid 21.12 21.97
Sulphide of iron .41 .09
Water 1.96 .39
Organic matter 5.72 12.98
Silicates, undecomposed by acids 3.03 16.69
100.00 100.00

This occurs with coal-scams which, though somewhat thin, are of excellent quality, and close to the mine is abundance of hue limestone.

Spathic ores of great purity have been found near Ashburton, Canterbury, at Foote's coal-mine, near the Miranda Redoubt (Auckland), and at Jenkins' coal-mine, close to Nelson.

In addition to these commercially valuable ores the following, which are only mineralogically interesting, are known:—

Siderite (FeCO3) is mentioned as occurring in cavities of the contorted schists of Otago, and also at the Clutha, but the writer is of opinion that it must exist in considerable mass at Hindon, near Dunedin, as a specimen from a vein, which the proprietors were working as quartz for gold, was found to consist of pure carbonate of iron.

Iron pyrites is exceedingly common, and is chiefly interesting, as usually containing gold, and being associated with valuable sulphides.

Marcasite occurs among the brown coals. Pyrrhotine was discovered by Mr. Cox in 1876, near Mount Cook, and has been found in various other places.

Melanterite has already been mentioned as occurring in the goldmines, and is also found in the collieries,

Manufacture of Iron.—Several attempts have been made to utilize these deposits of iron ore, the first being about 1874, when the Parapara Iron and Coal Company, Limited, expended £10,000, partly on the coal-mine partly on cottages and a wharf, and partly on the foundation of a page 54 blast-furnace. Their capital was, however, insufficient, and they went into liquidation without smelting any iron. Lately some 300 tons of the Parapara h æmatite has been sent to Auckland to be experimented on at the Onehunga Ironworks.

The granular ores of Auckland have several times induced capitalists to invest money in their manufacture, and many patents have been taken out for the purpose, but without avail. It is necessary to mix the ore with some cementing material, and for this purpose the scoria or volcanic slag, which abounds in the neighbourhood of Auckland, was at one time tried, but the result was unsatisfactory. The last company went into liquidation, and the plant was bought in by the mortgagees, who employed it in working up all the scrap they could get in New Zealand, and subsequently old iron rails bought In Queensland, which were re-rolled into pit rails. Some pig iron was made of iron ore brought from Whangarei (some 70 miles north of Auckland) by sea, after being carted 1 mile and railed 8 miles to port; it was then carried by sea to Auckland, and by railway 7 miles to the works at Onehunga. The limestone was brought from Kuiti on the Waikato River, 125 miles away, It could hardly be expected that this would pay, and, as stated, Parapara ore was nest tried, smelted with coke brought from West port and Greymouth.* The Government of New Zealand has not been backward in encouragement to the iron industry. In 1879, full particulars of the natural resources of the colony in iron, coal, and limestone, were circulated in Europe and America, and tenders were called for the supply of 100,000 tons of steel rails, manufactured within the colony from New Zealand ores. No offers were received.

In 1886, a bonus of £1,000 was awaiting the successful manufacturers of 200 tons of wrought-iron blooms, and the New Zealand Iron and Steel Company, then at work at Onehunga, was intending to apply for it. In February, 1892, the government made a further offer of a bonus of £1 per ton for the first 500 tons of pig-iron of marketable quality manufactured from ironsand in the colony, all material, fuel, and fluxes, to be the produce of New Zealand.

It is worthy of mention that the hæmatites found at Thames (Auckland) and at Parapara, are largely used in the manufacture of paint.

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Exports.—The official returns give the total quantity of hæmatite ore exported to the end of 1890, as 52½ tons, valued at £225, but Sir Jas. Hector's valuable "Handbook of New Zealand" for 1886, states that up to the end of 1885, the iron ore exported amounted to 209½ tons, valued at £1,066.

It will be acknowledged that iron ores of varying and sometimes excellent quality are widely distributed in New Zealand, and that first-class fuels and fluxes are often found in juxtaposition, but the scattered population of the colony and the cost of transport have militated against the manufacture. Wages also are very high, and prices in England and freights to the colony are very low. It appears to the writer that some of these factors must undergo a change before the industry can be started on a large scale with any certainty of proving remunerative. At the same time it is consolatory for those who have the welfare of the colony at heart to know that there are within its boundaries the elements of a successful metallurgical industry.

* The writer is indebted for recent information on the subject of iron manufacture to Mr. R. R. Hunt, of Auckland.

The Otago Witness of 6th June states that the latest charge is a mixture of Parapara and Whangarei ores, which will be run off early in July. Two Government officials relieve each other, night and day, to see that no scrap iron is put in.

(9) Platinum.

Scales of platinum, have been found in the auriferous wash of Foveaux Straits, and in other places in the southern gold-fields. Within the last few months its occurrence at Waipapa, Otago, has been noted. Platiniridium and osmiridium have been identified in Nelson Province.

(10) Sulphur.

Sulphur is found universally as a constituent of the metallic sulphides, and also in the pure state in large quantities on White Island, off the coast of Auckland. At this place it is deposited from hot springe, as on other islands in the Bay of Plenty, where it is found in smaller quantities. Among the Rotomahana and Taupo fumaroles some sulphur is found, as at several other similar localities. Work has been carried on at White Island, whenever the volcanic agencies have been sufficiently subdued to render it safe.

(11) Graphite.

Plumbago occurs in many localities, but never sufficiently pure or in sufficient quantity to be permanently worked. Prior to 1865, 7 tons of the manufactured article was exported from Pakawau, near Collingwood (Nelson), but nothing has since been done to continue the trade. In addition to this locality, graphite has been found in Wellington Province, at several places also in Canterbury, Otago, and Westland.

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(12) Petroleum and Oil-shales.

Though several localities in the North Island have produced petroleum oil of a fine quality, sufficient has not yet been discovered to render the venture a commercial success.

Three places have been noted for this mineral, viz.:—(1) Taranaki, near the Sugar Loaves; (2) Poverty Bay, east coast, Auckland; and (3) Manutahi, Waiapu, East Gape. From the first-named the oil has a very high specific gravity—.960 to .964 at 60 degs. Fahr. It is a good lubricating oil, but not suitable for an illuminant.

The oil from Waiapu resembles that found in Canada; by three distillations about 65 per cent, of good illuminating oil with a specific gravity of .843 is obtainable.

That from Poverty Bay is a true paraffin oil. That from Rotokatuku is of a very fair quality, with a specific gravity of .833.

So long as twenty-five years ago a company was formed to bore for oil at New Plymouth in Taranaki. A little to the north of the Sugar Loaves a hole was put down for 300 feet by hand-labour, and indications of petroleum were found with a little carburetted hydrogen gas. Another borehole was put down on Mikotahi Island, with about the same result Another company sank a shaft near high-water mark, and at a depth of 60 feet they were driven out by gas, having at 44 feet passed through a porous stratum with a little oil. For a few weeks, it is said, about 50 gallons of oil per week was obtained here. Recently an English company, known as the South Pacific Oil Company, has been boring, and in 1891, the depth attained was 680 feet, A little oil and some gas had been met with, and the boring was proceeding. The oil had a specific gravity of .834, and a flashing point of 93 degs.

The surface of the country is covered by a thick deposit of trachytic breccia, carrying ferruginous seams, and the places where indications of petroleum are met with appear to be included in a belt not more than 500 yards wide. In many wells about the locality small quantities of oil are found, but as yet no commercial success has been attained The borehole mentioned above was commenced 16 inches in diameter, and appears to be carried on by American workmen.

The Southern Cross Oil Company have been boring in the Waiapu Valley, Napier, for some years, and a considerable area of oil-bearing rocks of great thickness has been found. The borehole was in 1886 at 1,700 feet, and it was intended to continue to at least 2,000 feet.

In the Geological Report for 1888 is an account by Mr. Jas. Park, F.G.S., of numerous escapes of inflammable natural gas which exist on the page 57 east coast of Wairarapa North County, in Wellington Province, where there is a belt of oil-bearing strata from 3 to 8 miles wide of Secondary age, and consisting of shattered glauconitic sandstone, slaty shales, and sandstone, indurated marly and brecciated siliceous clays. It is considered, however, that the rocks are too much fractured to afford the requisite pressure for the condensation of the gases. A bonus of 6d. per gallon for the production of kerosene up to 50,000 gallons, in quantities of not less than 10,000 gallons at a time, was offered in 1874 and 1885, but no applications were received,

In addition to natural gases and oils the colony contains several oil-shales, of which the following may be mentioned:—

In the Chatham Islands is a bituminous peat, occurring in detached blocks of irregular form and considerable size, in the superficial gravels, It contains, after exposure to the atmosphere, 20.41 per cent, of fixed carbon, and 66 per cent, of volatile hydrocarbons. A similar mineral is found at the Auckland Islands.

A carbonaceous mineral containing 75 per cent, of volatile matter, and closely resembling torbanite, is found at Awatere, near Auckland.

An oil-shale at Orepuki, Southland, has the following composition:—
Per Cent.
Fixed carbon 14.96
Hydrocarbons 39.39
Water 6.74
Ash 39.91

It is found associated with coal-seams, and an inferior, but somewhat similar, shale has been brought from Blueskin near Dunedin.

(13) Clay and Sands.

Clays available both for building and pottery are so widely distributed that it is unnecessary to mention localities, and the same remark may be applied to fireclays, which, at Brunnerton, near Greyraouth, are manufactured by the Brunner Coal Company into most excellent bricks, retorts, etc. Kaolin is found in Stewart Island, at the Manuherikia Plains and Arrow (Otago), at Mount Somers in Canterbury, and at Whau (Auckland). Sands of excellent quality are very abundant, and in some cases they are sufficiently pure for glass-making.

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(14) Building-stones.

Building-stones of almost every variety, of great beauty, occur in various places; but their consideration is somewhat outside the scope of this paper.

(15) Limestone.

Limestone is almost universally distributed, Fine samples of marble have been brought from the west coast of Otago; but a company formed about 1880 did not succeed in establishing a business. Crystalline limestone is found in other places, agriculturally useful limestone at Toko-mairiro, Mount Somers, and many other localities; lithographic stones of good quality at the Abbey Rocks, Westland, and chalk at Oxford in Canterbury. Gypsum is widely known.

The above-mentioned minerals comprise, to the best of the writer's belief, all those which have been commercially extracted in the colony, with the exception of that already mentioned in Part L of this paper, and those to be dealt with in Parts III. and IV. Other metals and minerals have been found, and will now be briefly described.