AUCKLAND'S GOLD MINING INDUSTRY.

New Zealand Herald, Volume XLII, Issue 13031, 23 November 1905, Page 6

AUCKLAND'S GOLD MINING INDUSTRY.

, ORE RESERVES IN THE WAIHI MINE. ' WHAT THE LOWEST LEVEL SHOWS: A VAST AMOUNT OF QUARTZ. 1 THE DEPTH OP PAY SHUTES.

[by OCR mining commissioner.]

No. 111. The future value ;of a quartz mine lies in its low levels. That is why the conditions disclosed in the No. 7 level of the Waihi Company's workings liave such an important bearing, not'only on the Waihi mine itself, but on other mines on the same reef ■■ system, or in the same rock formation, in the same district. The fact that the Martha reef and the Royal and Empire reefs are as wide and wider in the. lowest ■ depths vet reached, and that they aro actually richer than in. the. upper levels, open's iip immense possibilities for the Waihi mine. • Not only, does this No. 7 level and the winzes and crosscuts connected with it definitely prove the existence of immense bodies of stone which can be seen and worked at any time, but it suggests that' other reefs in the; same ground can be depended upon to give similar results, and it further suggests that similar conditions will be found at still greater depths. It is in depth that we must look to the permanence of the Waihi mine . 1 and of others in' the same locality, and everything points to the conclusion that mining will- be carried on to at least' twice or thrice the depth yet reached. The Maria reef at 'Karangahake has been opened up to a- depth of 1700 ft from the surface, and is larger and richer at this depth than at any other portion. The Maria reef at the 700 ft level is seven or eight. feet wide. . •

.... The Martha ree-f at this depth is be- j tween eighty and ninety feet wide. I do 1 not mean to argue that because one reef is wider than another it is likely to live to proportionately greater depths, although : averagely this is a. reasonable supposition; • hut one can at least assume that the im- ' mense Martha reef at Waihi will go down as deep as -the Maria reef in the same class of country rock a few miles away, and, if this is I. the -case, -'then one can ! fully . expect that;, the Martha and other . Waihi reefs have another thousand feet "of 7 life below their present lowest workings, j Ijlie Maria reef at a depth of i 1700 ft is | really wider; and; richer than at any place ; nearer the surface, and looks like living ■ down another 1700 ft, arid one' can reasonably expect that it will, for other mines , have been worked to aepths of 4000 ft, and j the" reefs went still deeper. : ■

What does it mean .'for ! the Waihi mine if its great lodes : go down to such ■ depths J as indicated? It means, in. the first place, j »' tremendous extension in; the. length of • the reefs being worked, ; for at each level i below the summit of the Martha Hill there 1 is- naturally, owing to ; the slope of the hill, a; greater, length of}reef, to work, and in- No. 7 level/which is below the base of the hill, the Martha reef has been opened on eastward! towards ' the boundary of the Grand Junction claim, and could be followed ' westward to . the -western boundaries, of the Wa.ihi ground/ thus multiplying the length of reef, previously available many times. It means that the work- ( ings on the reef system, instead of being | confined to the radius of the Martha Hill, can now extend to the full width ,of the Waihi Company's ground, and if the great lodes go down to such depths as indicated • the; mine . can go on increasing its output of' stone, .and. still be producing great monthly returns; of ' bullion for many years to come. To understand V in .;' some degree what, amount of stone has been opened to sight by the No. 7 level on the Martha lode 5 it is only necessary • to reduce . the measurements ■;as given ; previously into tons.; Taking / the average ; width "of the; lode at '90ft, and the ..length actually ex-' posed at- 600 ft-,. with an. average height of: 150 ft, and' allowing 14 cubic feet to the ton, it would mean something over 564,285 tons. The reef iii the level above, how- ; ever, lias ,been proved for a - length of 1700 ft, and the presumption is that it willextend on more or less bullion-producing' ore for at least this distance in the No. 7 level, which would give nearly three times the tonnage mentioned.; It is not to be i ! supposed ' that every ton of this ore car- j ries payable bullion,; for even the Martha j lode varies in the value of its mineral con- ; | tents. ' In some places it is too poor to j be worth taking out, but what are called j the ' pay "shutes are . so extensive, and in some places so' rich, that they will bring the : ;bulk .of' this , sect ion - of the reef up to a payable average. If the same shutes of ore ' go down, as; there is every reason to • suppose they do, each 100 ft level on this section of the Martha reef alone will give about two years' crushing at the present output. * There;is also, as I have pointed out before, .the probability of other '"pay shutes; being opened . up along the course of the reef . to the east or to the west, but calculations in this direction may well be left until the reef is explored along its entire length within the boundaries of the claim. What lias been said with regard to' the ore reserves shown by the low level of the Martha lode may equally, well be applied - in a corresponding degree to the Royal and: Empire lodes, and even to some: of the other bodies of stone which have not yet been cut by the No. 7 level. New ; Zealanders who have grown used * to the rapid rise and fall of the surface mines in other parts of the country cannot realise the permanency of ; the big reef mining such as now. exists in the southern parts of the Auckland igoldfields, and such «s'-is bound f to come into existence : many other - parts . of ..- that auriferous and argentiferous region between the Barrier Island and Te Puke, nor can .they readily understand what this class . of raining means to. the community at large. I stated in a previous article that the Waihi Company paid a thousand pounds per day for labour and material in this country. ■ This thousand pounds per day docs not affect Waihi only. The mineowners and coal-workers at Huntly and [ the railway employees receive from it nearly £23,000 yearly. The timber workers : and timber millers in various places receive from it over £8000 per year. The limeburners . and the carriers of lime re-' ceivo from it nearly £2000 per year. And these y men, in their turn, spend much of this money in food and clothing, and such like things, which again means employment and money for those who provide them. About £180.000 per year is paid annually to men working in the mine and on the surface, and this sum spreads all over the .country.' f Tailors and bootmakers, jewellers,: bakers,'-butchers, and the hundred other industrialists receive the bulk of it, and all these industrialists go to the farmer for their butter and eggs and mutton and beef, and the other necessities of life without which they could neither work nor live. „ > ' < .;■ln company with' Mr. R. E. Williams, the mine manager, I visited the No. 6 level of .the Waihi mine. It is here and above here that the active work of breaking out ore to send lo the crushing mills is in progress. Here are the .stopes, : as they c are technically termed, where the brawny miners are busy with . pick and drill and bar, smashing the huge reef into fragments and rushing it in an endless chain of trucks to be hoisted to the surface. I suppose there are nc such stopes as these in the world, for, besides the immensity of the reef, the quartz: is so firm, the ground so >sound,;! that huge caverns can be made without danger and without timbering. ; I ■ eaw.' stopes forty ' feet wide \ being H carried on; without a ' single prop > to support .the roof. As can be imagined, j such stopes as I these require , some . filling j " in. Man • cannot ;■ take : Out ' these" immense bodies of ; quartz.. without putting some- j

thing in their ; place, so, earth and rock are 'sent from the surface and shot into the huge caverns from which the quartz has bee 11 excavated. The general rule is to always keep the stopes to within about nine feet of the roof, but,, of course,-this is ;• not always practicable, . and. in some places the roof .is twice this distance from the floor. ' To follow these stopes along the Martha reef is to gain an impression of its size,' which no figures or comparisons, can give. That small army of busy men working ceaselessly' are making and filling mainmoth caves, and yet' as one watches' them their labour seems like the effort -of ants against a mountain. Much of the sloping is done by contract, at the desire of the men themselves, and in this system ' one sees a striking repetition of certain socialistic or equalistic ideas. Under the contract ; system:■ quartz is paid ' for by measurement, and, of course, the more quartz broken out the more money earned. Some of' the more skilful and eiiergetic parties, when favoured by a run of easily-worked stone, make big wages, but -under this system the ■ weaker men go to the' wall, and:' under it, too, . even the strongest and cleverest ■ of ■ workers / sometimes strike < a hard patch, and this sort of thing brings down their average earnings. ; I have often admired the magnificentphysique of the New Zealand bushmen and their wonderful skill in wielding the felling axe from springy Jigger or swaying platform, but the Waihi miner can run them hard in physique, and swinging a ; big hammer against an overhead drill is more trying than any axe-work. It is a great thing to tear down a ninety-foot reef of quartz in the bowels of the earth, and to sent it surface-wards in small pieces, and these men do . it, and if • they v were pa-id by results, they would dig the Manakau Canal or pitch Mount Eden into Cemetery Gully, with the same, fierce energy. . The underground workings of the-: Waihi mine make a strange little world. Darkness made visible by little clusters of lights, and at each light centre, men -at work, picking, drilling, breaking off masses of quartz with bars,; smashing these masses with sledge-hammers, and through all this work wonderful order and : design —that spirit of organisation which lias made our race so supremely effective in its labours. The brains that . can plan, level and shaft, stope and drive, and keep the labour of'over a thousand men economically applied, without waste of energy, without waste of material, are such as have made us rulers of nations.

There is no need to puzzle anybody's brains with any description of the workings above the No. 6 level. Considering that there are over" 18. miles of drives in the mine, -without including reefs and minor crosscuts, and that the hulk of the drivase is about No. 6. particulars might he tedious, but it should lie explained that there is still , an immense amount of quartz, arid; payable quartz, . too, to be won from these upper workings. It may seem unnecessary to reiterate these particulars regarding the low levels 'in the Waihi mine, and one may be too sanguine in even suggesting ■ the possibilities before deeper sinking, but tho permanency of quartz mining means so much to this country, and the belief in permanency is so small, that one can at least point out what indications •there are in this direction, while at the same time realising full well that nothing which is uriproven in a mine can be anything more than conjecture. A shaft is, however, being rapidly carried down _ some distance below the No. 7 level, and is going through an excellent class of country rock. It is intended to' carry it down to a depth -of 300 ft below the No.' 7 level, and ' then ;to crosscut for. the purpose of intersecting the ' various reefs., ; When ..the sinking is completed arid the reefs opened up at this depth, something definite will be known regarding the value of the Waihi at about a thousand feet from the surface, and if the reefs are not still of an immense size at this depth, and if they do not -still carry payable shutes of ore, it will be a great surprise and disappointment to everyone who has studied 'the Waihi mine.-