American Tests of New Find Ore.

Te Aroha News, Volume IV, Issue 180, 27 November 1886, Page 1

American Tests of New Find Ore.

Me, Adams, manager of Messrs Firth and! Clarks Battery, Waiorongomai, who wenfr to San Francipc^ to report on the Californi.'in treatment of refractory ores, has submitted a report to his directors, Mr . Adams took with him some bags of New Find quartz Tho following are the most important enclosures in his report :— > No 3, October IG.— Lot No 3517. portion of sack mar Lea. D. NawFiud. The average pulp , alow. -i an assay value of :--Gold, l'OSoz, 22 dollars GO c^nts per ton : silver, 2L # 870z., 28 dollars - 28 cents per ton : total value, 50 dollais 88 centa ' vor ton. Thn nre coutains 13 3 per cent of sulphurolß and 07 per ci nt. of lead, JOlb of this oro way woikea by roasting and amalgamation aa folio «». s :— The ore mas roasted at first without this add it, on of an j thing until nearly all the sulphur hart been exuoUed, and then 3 per cent of Bait v\as added, and Kao cbJoridising roaßting followed In the last stages the heat waa rc.it,ed a lhtle, and about i of 1 per cent, of burned lime (about olbs to a ton of ore) was added, acd afcor ten minutes the oliame was dra-^n. The limo was addedto reduce the chlorides o* copper and lead, and ►■1.0 the sulphates to oxides, so as to obtain aa hi t ;h n grade of balhon a" possible. The result was that the silver Lag biea chlorodised to 89 per cent 'i ho i oastorl ore weighs 38 # 881ba ; lost confieqaen'ly 2 8 per cent, in weight ; and its assay value waa : Gold, 1 09oz. 26 dollars 60 centa poc ton ; silver 19 H- •/., 2"> dollars 13 cent 3 per ton rotal, 17 dnl'a-a 73 cents per ton. W£ had sustained a los 3 m ro'ißting of 4 dollars 48 cents per 1 1 t>a, bt ing (3d centa la >/;old, and 3 dollars So centa in tilver, caused oy voltatllsation, and l>ar<:<\lly ti3 r flue and dust. In vorking oa n largo scile, the creator portion of this loss can be onviaied by the meetion of flue and dust chambers. 'Ihisroabtid ore was now amalgamate d hot for four hour*, and we obtained 19217 grainb of bullion, *013 fine in gold, value 0 - 398 rent?, , and 522 tine in silver, value 0 426 cents. Thin is ayi Id of 90 percent, of the gold, and S7'2 per cent of tho silver obtained from the value of roasted ore, exclusive of loes susrniiied in roasting, and la a very good, jield Sow, when we include the j>os3 in Toastinc. calculating fiom tho oricinal astav valuo and weuht of The ore, we have* an outpuc of »foid 19 ("oilars 80 cents per ton, or b7"6 pi r cent of original as jay value ; silver, 21 (ioliuro 3) centa cor ton, or 75 3 per cent. o£ origi-mla*. vy value, malcintj a total yield of 11 do'lms 10 cents per ton actually obtained in bullion, ruda loss of i dollars 48 cents per tonr by O..SU-V Tho tailiiigd, upon careful eampmpr, cuuTdineu 5 uollarb ii ctn:s per ton., viz. ; gold.Oloz, 2 ('ollara 23 cents ppr ton; silver, ■^■3nz 2 r o.ifirs 98 cents pT ton.— Test of Thomas 'ueo, analytical chemidC, as^ayer, and bullion mc'tir, Stin tfrnncisco, Oct. 22. Tha bumytc marked D is co^ posed principally or qn.ii t/, cenThii.mg onlr 2 5 pc- cant, ot iron pynt- 5, arm yry smlo galena. This sample can on'y ro reimrGod ab a imxtid mineral, being an ..iKontiferous re mixed -ftith a free gold ore of low v<iiue. The ceonijja 1 jiu* report of the live -imnl-j; 'ination test will show that 37 dollars' 10 c^uta u<m- ton of 2,0001b i has been saved by bat^iy tuid oc nj.c- plat» amalgamation, outof a tot«'l value o£ 59 dollars 21 cents por ton. This is a saving :.f nearly 62 0 per cont of the whole valuo. in addition to this nearly 10 dolJars ."cr tnn of oi.jsical ore has bten stvved in the form of rich concentrates. Unfortunately^ hoAcv-t] 1 , over 20 dollars per ton passes into the ii iiines. (he proper methed by which to ue'ii siuh v re >-s this is as follows: An ordinary s'mni) mill saving as much as possible by uuiiil«amation iv t'.e battery, nnd on the copper o'a r e>j. co!>eentra'.iif? the tailings as they flow fiom the places on 15'ruo vanners. These concent ates should then be subjected to a chloridismg joastitig, and t):e gold and silver to be extracted by passing chlorine gaa through, the ore, followed by a leechinß u. dt.r water, ana feubs'.quent precipitation of the gold by moans of sulphate of iron (ferrous sulpnati-). The silver remaining in the residue to bt« lixiyiateJ with hypoaulphite of soda, and precipitated by means of sulphide of sodium. 'lhis nittnod of treating the concentrates will cost arout 12 d."llaifa iav ton, and will recover 95 per cjnt. of the gold and silver contained. Jhc c io concentrates could also be treated by sm-^ltuig with rich ores. As-ay of ore. dol. Gold por ton, 2"35-103cz _. .. Value 48.58 Silver par ton, B'4-10uz .. .. „ 10.86 Saved by amalgamation in battery and copper plates. Gold per ton, 1632 IOOOoz . . . Value 33.74 fcilver per ton, 2 6-lOoz 3.36 Saved par ton original ore by concentration. Gold vor ton, S^ IOOOoz - .. Value 1.82 fcilvbr per ton, 2-10OJ5 „ 0.26 Passed into tailings. Gold per ton, 03-loooz Value 13.02 Silver per. ton, 5*6-10 ok.. .. .. „ 7,i2 jis&ay of concentiatiOßS cmountinK to 2i p r cent. Gold tier ton, 3'5-10oz . . . «. Value 72.35 Silver pjr ton, 7 7-10oz „ 9.96