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Show PHE ANNIE LAURIE MINING COMPANY I itt1' tne most productive Kl!on 1 - camps to none Is It ln-"Trrlv ln-"Trrlv 'ns Is U to the founder., lflijlJ"llurf Mining company, H Ar'n!,' others to antedate niS"- 0,h0r9 10Cnl frWard Jt.r "bar of gold. Tt wss near-VU near-VU ago. indeed, that the r . ented the pre.-ence of the '. in that locality and while W" .nnclouslv lo It ever since It 'iron the purchasers of the WT .it 1. their superior resources, to '" V;1;,,. ,ra of systematic devel-f""1 devel-f""1 hl(h , a ledges have been n RrneroU,lv. With ! ' . ,lKht In this company and B150'"' .Ith wh, H has since been , I, an able and intelll-RiluSneiii intelll-RiluSneiii nev talent has been B ei.ier It" z-r "nd tho new B5"". ",h EoTr,e of the moslt for" BT Western companies In the B'IV. results which shall compare BLb'v3-"" th"" arh,eve(i by tnU B vors of the later organizations BIflit yr 19 ncm" qulte p0Blm' BsKTobout a half dozen year ago B vt pcP,,larlJ" characterized as Klr'bKh- Crowd" had its attention BJ the region, and; after an ex-KLtwn.lnntlor. ex-KLtwn.lnntlor. of the- Annie Lau-B",n Lau-B",n follow co by development Brifler not only nil that had been Bl'jS but InflniU iy more, ts pur-B" pur-B" consummated. From that Bfw rUurces have continued to B rntll at this time they are B" Se most stupendous in the B?of tho West. The development f i.xi fff months demonstrated Ltv for a mill and an up-to-Snt was ooor In commlsrton. Kr,t hour operations have bee Raw ar.d while the output has WF a.. to a tonnage compara-BrSgT.lflra.t compara-BrSgT.lflra.t in contrast with that BSL'out and awaiting reduction. It Brf.-!t out to Its various Interests BSoppmilmatlng $250,000. Dur-BTf Dur-BTf wst vear the management re-Bl re-Bl the wealth of 65 000 tons of ore. Kiting as many a 18.241 ounces m-.; , n ..: silver, the Hh'loga valuation of J406.226. Of Kc-m ther was distributed among BtMrvt-"''.' 'ht dividends, the BThi-h reached an een S100.000. Mr '. (hr c-plendid undertaking is In fekrv the record for which pro-il pro-il -Mure so happily endowed it to aid", with accessories greater than BTvrlth "hich It is at present Bftt? endowment of the mining in-Etry in-Etry with prodigious source of gold, I iur company has demon -ML-"its of Its own state at Bfcrly whlh town revels In the Kok of & veritable Gibraltar of gold. Bit b:i? Wlth fe'U:i1 mt?PT,ly- nf" Bd a lewon on permanence In the Ee camp that nothing can discredit. Kp gnld-bearing estate over which Breiririv s standard rises embraces Htsnhar.' i' ' " "'' ground in the M- " Hi- .... .ii 1 1 i ' ' "I" rn-Hfcsve rn-Hfcsve been aggressive the wealth bit a fraction of this valuable area Ab--i. fathomed. The feature ot ' 1 Kljtjrs operations and the supreme fcrerr: In the m r-ilgn of devel-HkcI devel-HkcI ihtre was the tapping of the Hat anrr of w:ilth tl.n.ijh No. ft,;, an rivf r.ue lh.it w:s forged Into ft ::r ;i , ' of 3h00 feet, and l Kkh the rharmi-1 of gold v. as tai'l"1' Bijici'.riT ut'd u)On a horizon 426 fr-et Hnrtban ai y r- ious workings With Hk deraonslratlon the management Rid ha9 Ku'll-; the r-g!o - --) i ' J - lias added not only immeasiire-Httto immeasiire-Httto Lr.e cn' ai", s :-t but it l.. s Hutsl.l an outlet for the ores tint Bt still flirt hr the cost of opera-Hh opera-Hh lr, the rev. tunnel the ledge re-H! re-H! i vldth of twenty-elKht fe.-t. the BnT- contents fully as pood us tin i -Bvbloh the management lr -u l-.-n gold dollars and dlvld Of th profits that respond to the needs of the Annio Laurie B shareholders sharehold-ers the cost of mining and reduction affords the most Instructive of lesaonL rhe log of the property shows that this has i now been reduced to no mnro than $3.50 per ton. with ;,ti ore of the value Ol ? tieltlng the company $6 50 per ton At present the product of the bonanza IB delivered through No. 4 turuael and tho mill has been enabled to hold Its pace under arjlng conditions much more e;t9lly than was post?lhli previously. previ-ously. After passing through the dryers, tho ore is elevated In a link belt bucket elevator el-evator to tho top of tho fine crushing department., where It is discharged over a BerthMot separator ln to a 6x20 Stur-teant Stur-teant roll Jaw steel crusher, whero ov- I - j A. E. Hyde, Jr., General Manager of Annio Laurie Mines and Mill. forwarded to the bins of th" mill over a gravity tramway, about 1S0O feet ln length, at the terminus of which It Is dumped Into a receiving bin, situated Immediately above a No 4 Gates crusher. Between: the crusher and the oln gate Is placed a grlzzley to take out the finest of the "dirt" and fo to prevent pre-vent the clogging of the crusher. The ore is delivered by tho tramway at the rate of about seventeen tons per hour, and the crusher Is adjusted so that It Is continuously at work all the time the tramway Is ln operation, usually sixteen hours. In this way no time If lost running run-ning the machine empty, and the ore Is delivered to the main supply bin ln the best possible condition for subsequent subse-quent operations Formerly, this preliminary pre-liminary crusher was on the ground floor, but early in the vear It was mov d to Its present lofty position, so that now no expensive elevator has to be maintained for raising and delivering the product from the crusher to the main ore bin. The ore, at thl9 stage, contains from 7 to 10 per cent of moisture, mois-ture, and. as the mill Is a dry-crushing one. this moisture has to be nearly all eliminated before further grinding and screening an take place. The ore from the main bin, therefore, is fed to Argoll four-tube dryes, of which there are three, all b. lng required re-quired when the or.- Is "wet." but only two of which are In use under ordinary circumstances. One of these dryers was installed this summed, and since then erylhlng over three-quarters of an inch in diameter Is reduced to this extent before passing to tho feed bin for the rolls. This bin, together with tho Stur-tevant Stur-tevant crusher, was put Into commission commis-sion at the Fame time as the new Ar-gall Ar-gall dryer, and is of sufllcient capacity to accommodate about one day's run for tho rolls. So long as the dryers are running and they are running practically all of the time this crusher Is ln operation, and. In consequence, the rolls have always a constant supply to draw upon. This means much ln the shape of Increased economy, for the margin of ore in this second bin Is sufficient suf-ficient to mako the rolls practically Independent In-dependent of the dryers, ami vlco versa. There are four sets of rolls, of Gates Iron works make, and. 1"'X3C In size, two of which are used as roughlng-rolls and two sets as finishers. After passing pass-ing each set of rolls, the ore Is elevated elevat-ed to the screen floors, where It passes over a Series of Jeffrey Columbian separators. sep-arators. These are simply large screens Inclined at an angle of about 40 degrees de-grees from the horizontal, and which are made to pulsate by means of an eccentric. The shock thus Imparted has the effect ef-fect of keeping the coarser particles off the Surface of the screen. While at the same time the finished product Is enabled en-abled to pass through. There are two towers of screens, and the oversize from each goes', according to actual size, to Its own particular set of rolls. I thero to be recrushed and afterward elevated el-evated and re screened. The underslse from the finishing screens has meanwhile mean-while passed through a screw conveyor, where It has been, sprayed nrlth cyanide solution, and so on to a conveyor belt, whleh discharges the pulp wherever wanted' In the largo pulp bin, at vhlch point the cyanide department takes It ln charge The motive power for tho mill and ml no ln electricity, and this Ih generated gener-ated at the company's two water pofer plants on Fish creek some six n il west of Klmborly. There Is also an auxiliary steam power plant at the mill, but this Is only operated In tho winter chemical test) it im diverted into another an-other channel and Wl to the precipitation precipita-tion room for separate treatment. The ore, too, tft it comes from the mine, Is to a small extent, arid In nature, and were this acid allowed to come ln contact con-tact with the cyanide in solution a serious se-rious waste of cinlde would result. As it Is, this acidity ln the ore i neutralized neutral-ized by the addition of burnt lime-stone lime-stone to the charge In sufllcient quantity, quan-tity, and, in order that this lime may be mixed wltn the ore mot thoroughly thorough-ly It is fed to on nf the rolls by means of a simple posltlvo plunger -Aorklng on an adjustable f-crer.trlc. Soon after leaching haj commenced, tho solution r I , t Annie Laurie MilL v srasori. when the water ln Fish creek Is too low to supply the requisite power. pow-er. TTansmls.s'lon of tho current from the various power stations Is made at 6600 volts, and the stepdown transformers transform-ers at tho ndll supply It to the numerous numer-ous Induction motors at a oltage of 440. Most of the power, of course, Is used up In the mill by the rolls and crushers but today the consumption of horsepower per ton of ore milled Is less than ever before. This is due, In a measure, to the amount of attention which has been paid to the problem of frlctlonal loss, which, ln a dry crushing crush-ing mill. Is usually excessive. During tho past year every bearing In the mill has been equipped with oil ring boxes of a 6peclal construction, and tho saving sav-ing ln every direction has been very marked. The ore having been crushed then, to a point where tho values can be most easily and economically extracted, it remains for the cyanide department to effect this saving of the precious metals. met-als. The gold, as It occurs In the Annie An-nie Laurie ores, Is In a "free" state, but It Is refractory In so far that only about 30 per cent of It can be saved by amalgamation. And when It Is taken Into account that there Is about nine times the quantity of silver, In the ore as Is there of gold.lt will be readily Been that the problem of getting an adequate ad-equate extraction Is not thereby slm-pllfledv slm-pllfledv The values occur principally In seams of the rock, associated with much oxide of manganese, but. at the same time, part of the gold 8 found disseminated through the quartz ln a state of line division, and this fact makes It essential that tine crushing be lesorbd lo in order that every p.n-tlcle p.n-tlcle of gold, be exposed to the action of the solvent In the subsequent leachr lng process. This solvent Is cyanide of I potassium, and the process In use Is known ns the MacArthur-Korrest cyanide cya-nide process. The leaching department has been extendod twice plne tho starting up of the mill In February, 1901, and Is now capable of handling 30o tons per day to advantage. The equipment consists of sixteen steel tanks, holding front 120 to 240 tons each, and with a total capacity sufficient suffi-cient to allow of from eight to nine days' treatment when running oru full tonnage. Each tank Is provided with a filter bottom of the usual pattern. cocoanut matting and 10-ounco duck and Is fitted fit-ted with from four to Jive Argall gate valves, through which the tafllnga are sluiced when the extraction of the values val-ues has reached the proper point. The ore is taken from the pulp bin ln tram cars and dumped into the tanks over a system of distributors, which prevents pre-vents the ore from packing, and at the same time spreads It evenly over the not torn. The benefit of this Is to be seen later on ln the Increased rate of leaching leach-ing and better displacement of solutions, solu-tions, which Is thereby effected. While tho tank Is filling, a "strong" cyanide solution Is, at the same time, making Its way up from below the filter bottom, bot-tom, soaking the ore evenly as It com-s, and not long after the tank has been fully charged with the pulp the solution solu-tion begins to appear on tho surface. "Strong" solution Is now run on top. and the whole Is allowed to stand for a number of hours with all valves closed ln order to make absolutely certain cer-tain that every particle of the ore has been permeated by the solution. During this time the gold and the sliver sli-ver have been dissolving, and when the leaching valve below Is finally opened, op-ened, the lsnulng solution is led by pipes to the precipitating room. Two different strengths of solution are in use, one being known as tho "strong" and the other as the "weak" solution; the first containing almut six pounds of available cyanide per ton, and the other about four Of course, these strengths are varied from time to time as the nature of the ore and laboratory test9 would Indicate. During the passage pas-sage of the strong solution upward through the ore, various minerals are met with which go Into solution ln the cyanide. thus rendering Inoperative part of the cyanide which was Intended primarily for the dissolution of the gold and silver. At tho point in the leu h-lng, h-lng, or percolation, process when this weakened solution begins to make Its ., ppi ,u I re i I being di lei mil '-d by begins to disappear fTom the top of the charge, and, wen It has completely disappeared, the surface Is gone over with a common garden rake to break ud the 5Mme and so allow the aeration of the charge to as great an extent as possible. Fresh, standardized solution Is ncw run on from the stock tank, and allowed al-lowed to percolate down through the ore to displace the former solution and. at the same time, to complete the work of extraction. This Is follower! up by more "strong" solution, and then by "weak" solution, each being taken cane of separately as It Issues from the leaching valve below. be-low. Finally, clean pure water from the water main Is added ln email quantity quan-tity and at frequent Intervals until no more cyanide Is left ln the tank, and then the charge Is ready for discharging. discharg-ing. Each displacement of solution, as has been Indicated, goes to Its respective respec-tive gold-solution tank, whence It 19 passed through the "strong." "weak." or "wash water" zlno boxes as the case may be. These zinc boxes are long, narrow, and comparatively shallow st6el tanks, div ided up Into compartments, each of which Is packed with fine threads of metallic z!m resting on a wire screen about two-thirds of the way down in the compartment. In passing through this zinc, the cyanide solution Is deprived de-prived of Its precious metal contents, which are precipitated by chemical action ac-tion ln the form of a black sludge or mud. which generally goes by the name of "Slimes." At regular lnteralg, the flow of solution through the boxes la stopped, and the slimes ln the bottom of each compartment iun out by means of a pipe and suitable valve at the bottom bot-tom Into a filter tank situated at the end of. and below the level of each box Here all the excess solution Is filtered off with the aid of a vacuum i ' pump, and the comparatively dry' H 9llmes are taken to the refinery for I furthe- treatment. The prei ipltatlon of j I the values in the zlnr- boxes Is almost perfect, even ln the case of the weak audi wash-water solutions, a zlnc-mer- J I cury couple being used in the box J H through which this latter solution; j I passes In order to aid tho precipitation.) I Much attention Is paid to the keeping i of the solutions normally alkallnsl through the addition of the proper1 amount of lime to each and every: charge, and; In consequence, the slimes, I, ln the zinc boxes are of a uniformly high grade. After paislng through tho J zinc boxes Into pump tanks Immediate-1 Iy underneath, both the strong and tho weak solutions are pumped up into J H their respective stock tanks, which are set somewhat above the level of the leaching tanks, and from ear-h stock l tank the solution is led to the top or bottom of the charges in the lanks re-quired. re-quired. In tho case of the "strong" so-lutlon so-lutlon where the consumption of the cyanide has ben most felt fresh solid cyanide l added to the pump during the pumping process In sufllcient mini -tity to bring up Its strength to stand- The first operation through which tho slimes go In the refinery Is acid treat-ment; treat-ment; sulphuric acid !s used for tho dissolution of the little particles of zinc with which th slimes are con-tamlnated. con-tamlnated. ami the process is conduct-ed conduct-ed In a lead-lined tank over which is j a hood for carrylrg off the noxious gnses. The slimes arc afterward washed with hot water filtered and dried In cast Iron pans In a large double muffle furnace. Then they Bre fluxed In ths usual manner, and melted down to bul-lion bul-lion In wind furnaces In No. 200 graph-lte graph-lte crucibles. Xo remeltlng Is done, but notwithstanding thl- the grade of bul- I Hon obtained Is usually about 940 fine, '! Of this. 240 pnrts are gold, 700 silver, end the balance zinc and copper lr' varying proportions. The time taken In melting nnd g'-C.Ing ready for ship- , mem two bars of 1250 ounces each is generally about seven hours But the tailings, meanwhile. ar I ready for discharging. The gate valves In the tank are raised, and a streajn of water Is directed onto the tailings through a hose and nozzle at ninetyi pounds pressure. Wooden launders underneath un-derneath conduct the tailings vto ths t plato house, whero they are pawed! over amalgamated copper platr-E, theni over riffles, ultimately finding thelri way to the main launder, which do-posits do-posits them ln a largo dam some distance dis-tance away. Sufllcient time Is given lr I sluicing to allow tho coarse particles of I gr id, which have only been partially dissolved by tho cyanide solution !rv J the tank, to como Into contact with the amalgamated surface of the plates and eo be caught. This gold, which was I! refractory before cyatddbsg, Is now bright and ln the best possible condition condi-tion for amalgamating, and, what Is more, It is amalgamated, notwithstanding notwithstand-ing tho theories of some to the contrary The fact that an additional saving of between 3 and 4 per cent has been mad Is sufficient evidence that the scheme is altogether a wlso one, as far as the I ores of thl company are concerned at 1 any ra'e. And, taking into consldera- ! tlon the amount of sliver present la tho ore, when It is stated that ths actual ac-tual extraction of both gold and: silver u comes near being id per cent of ths l gross value, it will be admitted- that ths j cyanldo process, as applied to the Annie An-nie Laurie ores. Is the one moat nearly suited to the caje ln point- j Than the management of the plant and properties of the Annie Laurie Mining Mi-ning company there Is, perhaps, no more efficient In the State, Alonxo E. Hyde, Jr., who was surrrmoced to tha head of it after he had served tt as chief engineer, has accomplished the most satisfactory results, and while h has the undertaking on & most practio-able practio-able basis, with every interest well la band, his unremitting endeavor Is toj achieve even greater results. As super-! lntendent of the mill ha has a most ab.er and a most conscientious assistant InJ Mr. O. Wiser, with A. W. Russell, th superintendent of the leaching department. depart-ment. Mr. Hyde, indeed, has every detail de-tail of the big proposition undwr com ! plete subjection, and all Interests, aa j well as tho neighbors, aro to be congra- I tulated. |