OUR UNDEVELOPED RESOURCES.

Otago Witness, Issue 1861, 22 July 1887, Page 12

OUR UNDEVELOPED RESOURCES.

5L KEMARKABLE AURIf EROUS FORMATION,

One of the Districts tflfe Otago Central WouW Open Up -What a Correspondent Saw "at Oplir — Green's Workings —An Entirely Hvw Departure in Gold IMsfcoveries in ©tago— S£n Analogous B&covery to That ;at the Shotover— Three Ounces a Day ' With the Cradle. "Recently I had the opportunity of visiting .-and inspecting the remarkable auriferous jformation&t Ophir, Central Otago» commonly iknown as " Green's Keef," or> to speak feiore correctly, as " Green's Seam WarAsirigs." This 'discovery was made, it ms,y l bc remembered, laearly two years ago, 3Jij(9, shortly after it was favourably reported on by Professor Ulrich, F.CJ.S. Since %Taat time Mr William Green, the lucky (proprietor (a very intelligent miner, and .perhaps one of the most thoroughly practical geologists in Otago), has been industriously "engaged in developing the auriferous '•resources of his claim, than which I suppose i fbh&re is not a more promising venture in all inland Otago. Gold has been found there under conditions which completely upset and disarrange all preconceived ideas and theories as to the modes of occurrence of the precious metal. A brief recapitulation-, then, of what I saw and heard may prove of considerable interest to all sections of readers. The deposit is being worked from an open face, as in a quarry, and as Mr Green < continues his explorations into the hill xrisiag in front of him, the existence teit gold as proved under circumstances in which it 'kas never previously been fonnd in New Zealand. Eecent diseovories of auriferous rock in the claim bid fair to eventually fulfil the predictions of Professor Ulrich in his report as to the extent and character of the reefs, leaders, and mullocky deposits, while the geological features as now reveakfd by the workings and further prospecting have become somewhat modified. iJftiree or four Sines of fissure or faults cross the claim, and tfchese fissures represent dislocations of the of considerable magnitude, and no doubt extending clown to the innermost recesses of the earth. Each of these fissures contains more or less rubbly quartz combined with mullock composed of seams of <clay and broken rock country, as. well as a good deal of free gold, and from two of the fissures quartz showing heavy gold is frequently taken. By ordinary miners these fissures would be termed "mullock reefs" or "\nullock dykes." The Most Remarkable Feature of the Situation is the altered condition o£ the rock country £ying alongside of and between the fissures, and its systematic impregnation with gold. In one portion of the claim the yock is a decomposed mica schist, intersected by numerous veinlets of auriferous quarte. These veins dip nearly vertically, but they are not very persistent, Running out and making in again continually. ITrom these leaders the innumerable rich extracted from the claim appear *o have come ; while the natural joints and yearns in the rock have supplied the nuggety, tree gold. Some of these nuggets weigh as much as 6dwt, are perfectly free of the faintest suspicion of quart*, with only soft talc adhering to the gold, which is usually ruade up of small plates connected by refcieuiations. The finest metal appears to comemainly from the body of the soft rock, without regard to either seams or leaders. 'The rock on the north side of the principal -fissure is a decomposed 'chloritic schist, is •'80ft in width, and is of a soft, cheesy consistency throughout. It contains numerous leaders of quarts, which are very persistent as to course and depth, and they all carry fine gold. This rock carries gold its whole \vadth, but Mr Green is unable to win the gold from it, owing to a lack of suitable crushing appliances. One interesting feature common to both the mioa anxl the <chloritic schist country and to the, veins and Tissures, in addition to their highly auriferous nature, is that a silicate of magnesia white, soft, and. finer than the purest chalk— acGottipanies them in tho form of nodules and veinlets. This characteristic has been, regarded from the first as indicating the location of large quantities of gold— in fact, it has not been observed here in any otb.er relation. The rock country as well as the reefs becomes more rubbly and muliocky at the crown of the spur, losing its usual stratiform character and, becoming harder, but still ■carrying a good deal of gold, generally in a iine state. "Floors" of quartz occur in the ••deposit, invariably a few teet thick and of circumscribed length and breadth. " These floors are all auriferous, appearing to be ■closely connected with the fissures and alternate with beds of soft gold-bearing debris. The Captain's reef has also been recently proved to be auriferous, many nice specimens having been broken from it. Mr Green has endeavoured to ascertain the extent, particularly as to depth, of the auriferous formation, and his explorations have satisfactorily established that the supply of golden debris is practically limitless. The mica and chloritic schists are gold-bearing for a width of 30 and 80ft respectively— fancy a reef at Saddle Hill 110 ft wide and carrying gold from wall to wall; what rosy times there would be for the shareholders !— and, as a matter of fact, it is hard to say where gold doesn't exist in the claim. Mr Green lately sunk a shaft through one of the floors of quartz alluded to above. It proved to be about 20ft in depth and auriferous, and it was found to be superimposed upon a golden deposit of exactly the same character as that above the floors. Several theories have been advanced to account for the peculiarity of this marvellous formation, and that which finds almost universal acceptance among diggers is that in prehistoric ages thermal waters rose and circulated in the fissures, particularly in the main one, permeating the rocks on each side, chemically changing their character, and introducing the remarkable supplies of gold. This would make the formation in some respects similar to that at Mount Morgan, Queensland, although it has at the same

time a mqlj 'ctos.e tf&femblance to the .'rich; discovery ireCeMy- made in the iSh'oftovei s -dtefcrteti The supply of •gold Would seetei Vo be practically ■ • &ncl if efficient crushing machinery veife erected on the d&lm it is believed the monthly retoxStfs of bullion \?o«ld be unparalleled ?h the history of gold mining in Otago. Remarkably iioh specimens are fre* i qttently met with in working, but fcheeS; can >' be no doubt that Mr Green {.OSes a 'largej 1 quantity of the precious «iietal owing *f,b Ihe] system by which he tMeavtlu'fs, ib M the splendid resottfl&s $ *hfe 'dla'iih to profitable | account to&ltag "ndtdridiisty SWemcient for the purpose. Thfe'ddpoßlt is simply sluiced in the '(W^iiia^y banner, the pieces of quartz U tffi& i r6bls: feeing saved for future treatment. i 6h Vb'ccasions Mr Green has extracted as A "much as \ Three Ounces of Gold Per Day Simply With the Aid of the Primitive 1 Cradle ; • and if the whole of the sfcuS were taketi on j i a face and run through a 'crushing ;mill, 1 1 firmly believe the returns would Ke such as] would cause the people olf Ophir to lose their mental balance.

I have endeavoured to give a faint idea of the pecnKari'fcies'of this wonderful claim, and I etoly hope the description will give my readers as much pleasure in reading it as was afforded me by my lengthy inspection of the formation. Nothing like it has ever 'Isteeh discovered in the colony, and I h&Ve good reasons for stating that when effective crushing machinery shall have been placed on the ground, the returns will eclipse those from any other claim, either past or present, in the whole of Otago.

I am afraid we have no idea what the diggings of Otago are capable of ; and thxise who know the condition of afiiatefi wi#L'&gi'ee with me that Our GoldfleltlK Have $'6i Vet Yielded Up Even a Tithe of Their Precious Sup* plies. With the veteran Mr Vincent Pyke, M.H.R., I have always held the opinion thai our diggings have been "prospected" much in the same manner that Chanticleer, in his eager search fc* ef&blfe litbits, turns over, the «ttperfiesi!l Covering of a manure-iiea!>.