Show MILLING MIL L I 1 N G AT THE SILVER KING by L 0 HOWARD M E before taking up the present millins practice at the silver king Co coalition altion a brief and general re resume sunie of milling in the park city district has a pace there have been two types of ore at park city in the main I 1 and both of these types are d disable into milling and smelting smelling sm elting ores in one class are the siver silver ores carrying a fair amount of gold but not very high in the bases such as those of the american flag and ontario in the other class may be placed the silver lead ores which also carry some s silver lver and gold enough in smelt ng grades to mane them bonanzas it is this latter class of ore that with some var actions the daly judge daly west and silver king coalition are treating the first class ore is ma aly a combination of the sulphides sulp hides of lead copper and iron with high silver value the silver lying in the galena and pyrite associated Associate a with the sulphides sulp hides there may be large amounts aini of oxidized material the milling ore is made up of the sulphides sulp hides des of lead iron ana anc in a quartz gangue and may contain oxidized material also at first the idea was to save the galena and pyrite and incidentally any copper sulphides sulp hides in the shape of or tetra hedri te and to reject as much of the w th the silica as possible today an attempt is made to save the zinc early methods at park city the first mills erected at park city depended on regulation methods for getting the silver of the oxidized ores these were followed by the comb nation chemical and physical methods and later caime the modern modera wet concentration the first mill built was the marsac in 1874 which was equipped with twenty stamps and worked on flagstaff ore two other stamp mills of the same size size were soon erected for the mchenry and the ontario somewhat later all a three mills were at work on antar 0 ore the ontario mill was enlarged in 1877 and was equipped for a process involving dry crushing chloria zing roasting and pan on a process more or le less ss common non at that time the ibe machinery for which is familiar to fillmen mill men in the early ligh eighties tes the marsac mill was enlarged and devoted evoked to custom ores it was here that the he well known russell lixia aaion process for or saver ores was developed the pres ant it attempts apts at developing new methods for flie e silver ores of the camp are interesting in beof what at has been done in in the past meanwhile the mckim makr m concentrator was developed deveo Ped and patented in 1876 and ran from born 1878 to 1880 making makin the first real at tempt at wet t concentration in 1886 a num ber r of frue banners van ners Hunting tons rolls rock crushers and screens were put into the crescent mill giving it a ton capacity in 1889 the unon union plant was bu it in empire canyon with a similar capacity cap acty the mayflower plant followed this in woodside gulch treating 15 ore and the union gave up custom work to treat the anchor ores success with these concentration mills resulting the larger companies put up plants the daly west in the middle nineties the daly judge in 1902 and the S iver king plant went into commission commiss on before the daly judge several other plants have been built since that time but since this plant is the one now treating silver king ores I 1 will not attempt to consider the other plants at th s time 1 A rm I 1 h al the silver king sampler higger S original silver king mill in june 1901 the silver K ng mill was equipped with a ton sampler and an aar aerial al tram iram leading to a load ng station at park city the sampler and tram will be described later the mill where the second class ore was treated contained at th s early date equipment which made it one of the most modern concentrators of the time the plant was bu built lt in two ants air ts and a part of it i 1 4 so operated today the early plant contained in each unit a blake crusher two rolls automatic automa tc sampler four more nine jigs dewater ers two huntington mills ten wilfley tables two cassi c classifiers assi fiers five frue and four wilt wilf I 1 ley sl imers boutwell describes an interesting feature of this old mill has since been abandoned he says the method of recovery from the slimes is by forcing them through a filter under high pressure from compressed air the machinery required includes almes sl mes settlers slimes rece recovers cevers re vers a r receivers air compressor a slime press slime cake cutter belt conveyor and cummer drier the slimes which carry sufficient material ma teral to warrant further treat ment are first passed through a seres of s x V shaped settling tanks the settlings are then drawn off and elevated to a stock tank whence they are released to charge two receivers of 2500 gallons capacity thence the settlings are driven by compressed air into three filter presses one of 1400 pounds capacity the others of 2000 pounds ca pac pa c ty after being subjected to high pressure the slimes are dumped on a belt conveyor transported to a chopping machine thoroughly chopped and then subjected to a high heat they were then sampled sampling ng silver king ore I 1 have ment mentioned boned in the description of mining practice at the ithe silver king the fact that first and second class ore was kept separate the first class ore is hauled a short distance from the king shaft in a covered shed by a motor similar to the ones used under underground round to the sampler this sampler s one which would do credit to an up to date custom plant and is one of the best I 1 have ever seen in service at any m ne the ore is is dumped at the top of the pant into four ton bins whence it is taken by belt conveyor to a grizzly the overs ze of which s crushed in a comet crusher to I 1 inch it then fals to the first of five elevators set side by side on a floor below the cri crusher isher this elevator fats the crushed ore to the first f four our vezin samplers set side by side two floors above on oil the floor below is a battery of three sets of rolls the reject from the first sampler as well as that from the second goes to no 2 elevator while the reject from the last two are conveyed by belt to this same elevator twenty per cent cuts are taken and the sample falls to the rolls below is crushed re elevated and sampled tile the cut falling back to the next set of rolls and so on through the seres ser es of rolls and samplers which cut four times the last cut 0 o ng to a coffee mm mill further crushing and sampling being done by the earnil familar ar hand methods professional Profess fonal paper 77 V U S geological survey the rejects from the various samplings are elevated to a rotating spout delivering to three bins which feed the buckets of the aerial tramway and are delivered at the railroad tracks at park acty feet away the cost of sampling is cents per ton of ore and concentrates sampled in this plant is a concentrate sampler also the concentrates come from the level below the jig floor of the mill and are crammed to the sampler in one ton cars there they are elevated to a short conveyor discharging on an apron about which travels in a vertical plane an endless chain carrying two buckets which take a sample as they pass under the apron and as they turn to go across the apron above discharge to a chute which delivers to a sampling plate on the same floor where the concentrates are further hand sampled the rejects fall to bins below and are sent to park city over the tram the sampler is operated by six men meir power is furnished by a 75 horsepower motor driving a line shaft from which counters are belted for the machines the arrangement of machines of the same type on the same floor facilitating the drive the aerial tramway the crude ore and concentrates after sampling are sent to the railroad at park city over an aerial tramway feet long this tramway has solved the entire transportation problem as all supplies are sent to the mine over it also it is of the leschen patent automatic type and is supported on thirty nine steel towers 13 to 85 feet high eighty buckets with a capacity of pounds of ore or pounds of coal are fastened at intervals of feet iby by permanent perm ament lugs the running cable is 6 strand 19 wire langlay lang lay 78 in in diameter and of roebling make extra strong cast steel the leschen track cables furnished with the original equipment are still in use they are inch and 1 inch in diameter on the loaded and unloaded side respectively the total fall from mine to lower terminal is 1050 feet and the tram operates operate s by gravity generating 17 horsepower with no return load one man loads the buckets at the upper terminal and the buckets dump automatically at paricity park city tramway operation during the last fiscal year cost 64 cents per ton of ore and concentrates shipped both crude ore and concentrates are loaded on railroad ral ra road cars at park city and shipped to the smelters shelters sm elters in the salt lake valley the silver king mill As will be seen from the illustrato ons both the mill and the sampler are of the extreme hillside type the second class ore is brought to the mill by the same motor that hauls the first class ore the mill being located further along the ir hi 11 ll from the shaft than the sampler the ore now being treated is sometimes a lead carbonate carrying in silver in a quartz gangue at other times is a diluted sulphide ore the flow sheet gives the details of the treatment so that I 1 shall confine myself to giving a little further detal on certain bertan parts of the process up to a month or two ago the ore was taken from the receiving bins in one ton cars weighed and dumped to a gates crusher the similarity of this to the original mill is apparent the gates took the place of one of the blakes and the crushed ore was as conveyed by a short belt to the bins above the line the gates now does all the crushing and in additon addia addit on three men at the belt sort out waste and crystallized galena which they throw behind them into different cars the first class thus sorted is weighed and ee elevated to the haulage level above and taken ggs as shown in now flow of which those treat treating ng the first two sizes alone make a coarse concentrate which is drawn off the screen all make hutch products tails from the first three sets of jigs are ara de watered in a paddle wheel and an d reground in traylor rolls one roll of which is fed across the f face ace of the bhe other for a d istance distance of one half inch these rolls are set to crush to 2 mm and replace the 5 fact huntington amill which was operated with ivah a 6 mesh screen until a short time ago they will crush tons of 12 inch undersize in eight hours the tails from the jigs treating the last oversize and the heavier por of the last undersize are sized on oil a 12 mesh sl single callow screen which also receives the heavier portion of the overflow from the watering de wheel after it has passed over a chip screen and through an 8 foot callow cone LF L F V A N 01 the silver king mill photo by will C higgins while the waste is elevated to the same point and crammed to the mill mil dump the conveyor belt is too far below the bin gates to allow the ore to fall on it A movable feeder mounted on a truck con fists of a motor driving through suitable gears a set with its axis parallel to the belt travel the ore falls on the outside of the and is s carried away from the bin to an apron which discharges d on the belt coarse concentration the crushed ore from the bins is fed to two tron unel lines consisting of six each the oversize from the first is crushed in rolls and both undersize and crushed product elevated to the line again the second tro mimel is also a reject the overs oversees zes from the four remaining go to 2 compartment hartz table concentration the reground y i g tails are all made to pass through a 2 mm callow screen and the material remaining on a 12 mesh screen is roughed on a garfield table which rejects tailings and passes the to the so called tailing elevator which also r received e the from the Wilf leys which treat the 12 30 imesch stuff and the from the wilfley treating the second size from the V classifiers and the from the Wilf leys which retreat the from the remaining primary wilf wil leys the fine jig fig tails 30 mesh are classified in a V classifier which feeds nine Wilf leys the first four of which make finished concentrates and ta takings lings the n from all but the second group of three going to another set of V tanks in the slime department second alie C cais in tor 7 garfs joao ton hf bet ecea ec ef eq aele neof about bout ZOO borlet fee t lo locq J C crr iz aly V vo f gam G a m 3 1 fea H e I 1 IQ 81 8 sele sefe condor Co re feed bm ao al 0 f y 6 ee abor com ZAO we y art 1 2 ts 3 ios 1 7 7 7 va 3 trois 1 11 buik c uj vc fth concentrates rates raie esal cyric s cones cacs 1 ahle agn c s 7 4 ec e C cot J f ys 95 jhc sace ve e to cor co conca acx r r 1 Z ya e Is 3 6 toya ad ar Z 4 auf az aci A S h hoef I 1 le to t C car P D ro 4 I 1 P co n cc pvc C S S cc bencs acs I 1 S C rew coa conveyor v e Y settle S f 2 ao E e va or ys sa TO 7 da Z 2 etc purva CO cr cor etc 0 o E f avatar Z 2 coy C artz J ys Ms 6 7 ries Z H th t h fh Ju junery jery ee ro no af 67 1 2 2 se Seers ile s 4 T sy ajo rr 0 0 o I 1 sea Z 4 Z 2 com conay ori J QS lajou core cone lop 4 i REH RE e H callow con es I 1 S I 1 2 mn co ca c IMI S c ree reea 6 AYO bat Z byc 9 yc A 17 12 baileys ys Y ft ca cone I 1 I 1 fm pump I 1 r 7 Z tn ej C cacaj Cac C uj J scree screens as CW e r L 1 ct Ws PJ gart eld aale 7 ale 12 cohew cc sc I 1 W x j 1 1 7 1 jy Y ado ter ai aa cs fi casaul con e Z Q etca su con ea ao 0 besl cohew screen I 1 avi W aele ey Y 30 6 resh mesh CC screens sc e s 1 i 1 i 1 3 C 5 I 1 S V CIO cosser J 1 er 1110 M Ws Ms s to is 2 8 fl fe C callow 1 I cones cone s i 4 va beyt 3 i eyt ial ey I 1 wa Y finif ump C AWs tai L C 11 bics yi cs cones mid J ids 1 r M lda arc roll f 0 I 1 wo aja ter 11 T md ad lid pump beyo for f or L ta ce cious Cio da uj S mcfee C jle e i rm cp ts C P Z co 01 Z Wl feys Z jiey Y s diey Y ec Y S er coye 0 ory 17 ea eft I 1 cones wid cju tofe cones jofs ar 01 cn J J a C 4 F J J Wih leys rails 2 2 V lab C la w ads W k lits lla i 8 V a cacno 11 W ley iley I I 1 A W L aile tle I 1 12 2 eft e 8 ft fl coe coes s cao C W C cones t 3 W tais aaa I 1 V s I 1 C ds d n i 1 to levator wafey wo lash sh wd e e r settler seer ae t 15 I 1 US i 1 if ley FLOW SHEET C I 1 bif tifa 2 M ILLS ILL S L VER KI NG COAL COA L ithon MINES MIES CO P e r we 0 1 er poy po pa y C acty L utah t 6 h YV ot 18 igi 93 3 the untreated fine material from the classifier or settler below the line is thickened the overflow going coln to the slime V tanks and the coarse material feeding two Wilf leys which make a concentrate and which go to the slime classifier all of the coarse which have gone to the tall tail elevator are again screened and coarse material is treated on another hartz jig whose tails go directly to a wilfley table for the 30 biesh esh material is thickened and passed over three in series which continue the re treatment of the finer which have gone to the second V tank are treated on five wil fleys aleys wh ch make finished tails and concentrates and send their hack back to the tailings elevator from which point they are treated further slime treatment all the slimes from various parts of the mill are treated on wilfley m multiple deck slime tables of which there are two in ill operation era tion one treating the last spigots of the second V classifier the other treating the from the first and other slimes as shown on oll the flow sheet handling all the table concentrates are settled in boxes at the ends of the tables the overflow water e going to the second V tank the concentrates a are re shoveled to cars and tram |