THE OPHIR REEFS.

Dunstan Times, Issue 1241, 11 December 1885, Page 2

THE OPHIR REEFS.

The following is the report of Professor Ulrich to the Minister oi Mines on Green’s reef at Ophir University, Dunedin, November 23, lsßs. Sir,—l have the honor to inform yoa that under the guidance of Mr Green, Mr Pitches, Mr Bannerman (agent for Colonial Bank), and other gentleman interested ip the Ophir district, and who gave me every information desired, 1 inspected Mr Green’s celebrated gold discove y, as well as other occurrences bearing some resemblance to it, and also the drift depo-it at Ophir and Blacks No, 2 and No. 3. The results of my inspections are as follows

Mil GREEN'S AURIFKROC3 DEPOSIT, This is at present exposed and prospected for a distance of eight or nine chains, and in one place for a width of near 30ft, run* ning at a strike of east lOdeg, N. W. lOdeg between two gullies, acrois an intervening ridge, which is about 60it in heigh . Near the top of this ridge, on the eastern side, are several old shafts, sunk by former prospectors, and it is here where Mr Green first found the richly auriferous quarts specimens (the auriferous character of the stuff which is presently to be described), and has so far carried on most work. The stuff composing the deposit consists of a thinly laminated, decomposed, soft, and friable metamorphic schist, probably orUia nally chloritic mica schist, showing a nearly horizontal bolding, and being more or less abundantly traversed in all directions, from horizontal to vertical, by broken quarts veins, ranging from a thin thread up to an inch in size, and soft, white mineral occurring freq iently in irregular small patches and veinlets proved on examination to be silicate of magnesia. The color of the de* composed schist when frethly broken is greyish blue, bat fades quickly on exposure to the atmosphere to a bluish while, interspoised with brown ferruginous spots. According to Mr Green’s trial washings, and some executed in my presence, the gold is distributed through the stuff in spongy crystalline particles from the size of a bean down to a state so fine and light as to be hardly recognisable by the naked eye and scarcely retainable in the tin dish. Besides this it occurrs in the quartz veins, especially those with a steep or vertical ; dip, some of which have furnished specimens of great richness, consisting in cases of more gold than quartz, and a few which Mr Green showed me would, if the quartz wars broken out, yield small nuggets from several pennyweights up to [perhaps nearly ao ounce in weight. Owing to the irregular distribution of these auriferous quartz veins, it is impossible for an estimate to be made of the gold contents of the stuff in the average ; but so much can with certainty be foretold, that, should the ground on further exploration in a strike and depth prove' as rich, throughout as at the place' about the old shafts, Mr Green will soon become & very rich man.

Regarding the geological character of the , depo-it, and what it represents in a mining - point of view, 1 was enabled to make the following observations An open cutting between the old shaft shows that the soft stuff is sharply cut off on the south side by a hj ard quartz vein a few inches in thickness dipping N. 10 leg W. rather unevenly at an angle varying from 60dog to 70deg. Beyond this quartz vein, which is called the “• Captain Reef,” and for the prospecting of which old shafts have been sank, follows a thinly laminated micaceous quant schist, showing a nearly horizontal bedding. The quartz vein has mostly been removed out of •' the qnartz schist, but at one place a patch is left showing a finely p lished surface with deep striatums normal to the line of strike—a so-called slickensirte, whilst the ends of the laminations of tne soft stuff are slightly turned upwards on the quarts veins. Whether towards the north a similar wall exists has not been proved as yet, and nothing can be seen on the smooth surface for a distance of about two chains, where air Green has prospected with fair results of lino gold. From the gully upwards to near the top of the "ridge is a second vein of soft decomposed rook striking parallel to the first but showing a lighter color, and more abundant and larger feruginous patches. Adjoining this further northwards follows a chioritic mica schist, which, though soft in the euily through tho ac ion of tho water and richly with pyrites, becomes soon hard ridge, exhibiting their massive crops. From these features,

- ■ gVa. . A*- - conoieliph wjth- olheri.'qlea# evidence is *ffordsdby4hesecond«i>leandth« adjAin-.t-jh* quarUeohislftjiat lathe line of the )iaf of the CaptaiqJlreef a fselVhas taken, plica, with of » down-throw found at'Bkipncr»Gr««k.»odo*uy places in Vio. torSa ■•-Tit rook and|iti waters once circula! mg in these fissures—a hypothesis for which the fact speaks some wfytt.jn ffyor <|| the Richest ep- oimens and the besiprospectsf loose gold hiving been obtained by MrGreem close.along tba Cap- - tain reef* along which itself has so far not ; proved gold'bearing. • Judging from similar occoirenees ih of the , fine gold is derived from decom-_ - posed auriferous pyrites, an ore whioh a°y likely occdr sr ATich impregnation- of the' , topk'in .Jibe, ;d«mUi brfftw.. th®- permanent level.: ,:Taefc«ftfr ’hardly bts a' ‘doubt that the-fault,with it-the deposit ••thi'cmgh strlka. is greater than at present' tHS^'s^^eralohaihs.to; the westward,; .ton the Western side'of another gully, M?,. t tinea obtained frbmia greenish rottenrock ■‘fair prospfecjta orifiqe gojit- of a similar' character M - c&Au'rring‘htt u tha' i 'Eoft rock of' his .^ard-wouldi- boweypr,- he cjhmoted with i‘,difiicaliies, f ai.tha ii'pc pf strike of the fault' « runs across a-drift terrace into the flat, and extends through' the T township of Ophir. . Towards tha'quithe chance of the extension .x>f-tfia deposit at least of the same width, •<me«ton unfavorable,-as the ridges in that die reetion showing thw'diho-bf strike .of- the 1 . f suit art- pificrops pf hard metamor chse' together? ~ t-a : Regarding the ixtrAotfdu of the gold from r the mullock* the -softness: and friability of /the latter permits of its quick conversion, fine'thud by the action of water, and’ ." therfifpr.e the a- piiddling machine and a plentiful supply of water, and the crushing of the;quartz portion remaining in the mill, biy opimon. b'e' the most ad.viseb]q..pcncess;to adopts ■ Since Mr Green’e discovery several places showing similar decomposed rock have been tried on. the ridges in different parrs of the 1 district, but apparently without success in - finding payable gnjd:. «j.„ , ;». • . A place jailed M’Lead’s Working de serves, 1 thi k, some further explanation, ' as the ruh'of tofcteh' rock seems’ to strike pearly in thd 'tame direction as that of GrAep’s Sufi proapecta'of fine hackly gold qrq said in be ob,t*iiiibte from .it by the tin dish, trials.Considering the ..great scarcity ot qifarTz .vef- in the'district,- in oonjunc ; tian. with£be fact’tfihf there are 1 a number of surface workinea and dry alluvial gullies !i higkabove the boundary line in the raountai^.w^oh.hijjtp^iflied.payable told from gravel with ‘vefv poor appliances acid small Capita), if ah efficient' water supply were brought down from. Upper Manuherikia {which I. was told would' he the most advisable course), on to the,range above Ophir it. would not only permit the. hydraulic sluicing'of all the' township, but would, lead Ho doubt also to the discovery of other high drift deposits of equal richness in quartz. It is highly probable that such,gold was derive! from mullock deposits similar to that at Green’s. I.he district, therefore, cer %iinly deserves more extended and systematic prospecting.

THE DRIFT DEPOSITS AT OPHtR AND BLACKS . , rL . p'S. g. ANp '3.. .... Eeaarding these, I cordially agree with Mr Pyke that they are unjustly neglected; and off""'excellent chances of rich retains to enterprise. ’ Lower down the valley, towards Alexandra, the workings at Blacks Nos. 1 and 2,- now nearly, abandoned, indicate. as Mr Pyke says, the existence of a genuine deep lead ; but examination of the ground and information about the depths towards the broad Ida Valley, in .which no doubt a deep main lead lies hidden, are required.. The two branch I eads start at Blacks No. 3, very shallow from a saddle Between the - main range and an isolated outcrop of metaniorphic rock, and runs for three-quarters of a mile down the valley along the foot of the range towards Blacks No. 2, teaching gradu. depth of over 100 ft. The other rims up the valley, curviog towards the latter, but reaches already to within a short diet nee of the last shaft worked from a depth of close upon 200f. This shaft, according to information kindly given me by the Hon. Cap fain Fraser, who was ptereste 1 in the claim, was abandoned <m account of a bo ly of water breaking into it, and. from tlja veiy limited workings nearly L2OOO worth of gold was obtained. About the result of workings on other lea’s, Mr Pitches, who knows the tiejd; m« timately since its opening, gave me a most favorable account. , Payable and even rich gold was founddn moat of the claims—as much .as 40oz a-day in one case —and the lead was,not lost. Only,the great expense of timbering,, occasional trouble, with breaking.™ of drift; and principally, the, rush to the West Coast,,led to the gradual abandonment of the field.. Not doubting the cor* reutnoss of all the information given, ;I can only say that if sneh a prornisi>" nl-'/'o we r e •in Victoria it woull be rashfd directly I . only, requires several parties ui stalled miners with sufficient capital and one or two well managed companies to recom jneiice'working, and 1 have no doubt that, this deop-lead field will again, become prosperous and.attraqt.a large population, th» ippre so as" there -is' every probability of* similar branch leads and Surface drifts as those existing and being opened nip along the as yet unprospected; foot of the ridgeßigher np the yailsy.-i—-