Show ABOUT record QU kindl give apace ui bour valuable alu able paper to a few remarks and suggestions on the g etem of concentration as at present adopted in this district before pro acceding further allow me to preface my may be drignat ed with a few w on the nature of tion to begin mot mining know that it means alie of till ore or mineral from tl c gangao or waste that BO tar as known in tt is age can only lie accomplish cd in a i ro bitable way by grait tins aung tl e case the first step necessary is to chuh or granulate the crude ore to a eay fine enough to all piss through a inch 1 ole or 4 mesh to 1 of sarun it must tl en bo sized for without caie ful ai d exact sizing like cloe clo e or clean concentration is a downright impossibility all coarse crushing mills or ideas to tl e contrary some pard cilar orea ma be concen 1 in a ie w b coarse chrusl ing 1 ut it is a safe asur tion in say ing they are er few tl ere being tw 0 general matl of sizing let us look at tl cm loth as exact sizing ig tie cital part of the entire process birst tie tl 0 hydraulic sizer wl ich dikners alie ore in cul es of nearly equal t but not in nearly equal bulk second tl 0 original or which doglii erg in nearly equal bulk or size irrespective of weight or gravity the are fa oral tor tl is rea son I 1 cube or particle of ore in 1 a cube or particle of gangue both being elameen ent specific gravity and an well con strutted ted or mountain g will separate tic cubes ii a iery satis tory wl in tie case of hydraulic siang two cul es of nearl or the same gravity irrespective of size fed to any kiihl of a j acan not 1 e clean y separated V j g is not humin and can not discern Ife tween the pieces and both bin g tl e same or i early die same t will consequently either be re tamed or rejected alie result being 1 agh or rich tailings ai 1 poor or er difficulty now wl icci must be overcome as two prominent mines in tl is district produce an ore in which it is found tl at the contents of tl e inch cubes before mentions nc 1 arc composed of two thuds gangue an I 1 one third mineral aal wl ich will naturally I 1 c thrown off b adv good g conic bently finer is ncncy try the motile tor aging leaoro final crushing la hit nearly of the cm ie ore is marketable with out far tl er chrusl ing tl cereby braung t e ex of unnecessary i e tl 0 ig tailings can be put aliro igli a hunting ion centrifugal i ul tl at mad me at present being tl e only b ic nal of tl 0 stamp 1 atler and chrusl cd to pass tl dougli a 30 or a 50 screen g to tl e nature of theore and in ninth state it ia leady tor treatment on any impi oed reliable belt table of which tie fiad I 1 jhc triumph oldbury and ers laa re cor la of cars of satisfactory re s ailts table gs as a rule consist maidl of fand and slime tl e latter car agui slime concentrator has as jet baui 11 ente 1 1 arang tl c leek which is AS tt in its infancy incy but tie gai I 1 aal slime can lie separated and tl e differ grades of slime settled an I 1 a itoman clr boffin m arr ain factory manner 1 y means of diries cf dermal tl e water aiom ahu h aa a rule being cleir enough to I 1 e leburn us an important item in districts wl eie water is carce s tar as mac anery is conc crne i it is w is dom before deciding on any particular macl ine to 1 ae some careful tests male firt to ascertain tie ore is pr opeil a coi ore nc ond wheal ent is adapted tor tie coaree or fine process tl ir I 1 whether tl e ore 0 eglit to be treated y amala nation or first aal alie 1 baier minerals concentrate J afterwards out by a secondary process in an bent each machine buet be properly adjusted to work 11 e I 1 ore it kiy bo called upon to treat for instance a jig ought to be so arranged that bogli stroke and speed could be adato 1 tl e construe tion of a power ug is invariably BO so tl at tl e etrone can bo but it is not an uncommon tl ing to see tl e machinery of some new mills een in in tins district arranged so that altera tion of speed is impossible without ie construction grate error is tl cereby committed for it 14 an fact en a g is g ore through a ti inch mesh it 11 a much long cr stroke aal glower speed than alen working ore tl at las based through 15 or 20 mesh screen the in pulsations between tt e two extremes may be ai proximately speaking nearly doul lc ono other fact in baior I 1 fine i ulver izing IB the getan g n 1 of a large portion of tl e objectionable zinc BO prominent in park city ores an 1 wl ich being held mainly in the shape of zinc blen ie is free aa a rule from conglomerate in the ore and after fine ing its specific gravity being approximately galena zinc ab its separation 13 more easy eliat wl en in distinct cubics any mill that discharges tailings coarser than would pass through a 10 or 12 mesh screen roust 1 eife n large ige of tie mineral 1 dl in tl 0 original crude ore numerous Aum erous in stances en finK this fact are to be seen in the huge tailings dempa wl ich are pled up at most mills some of which at alie day are found to be rich enough in mineral to pay to ye shipped to a smelter after rondii ig are fit for tl e furnace An nony in a low grade proposition ia anoil er great an 1 fur that reason a mill eli nl 1 allaf it atall pos sille be on a hill tile BO that tie crude ore will of its own brauti asa from one edaa of treatment to anoil er without tl c aid of pumps or eleia both of winch are expensive nuisances and to lo 10 alidel if possible n adequate supply of water is also an absolute abo lute necessity for tl e successful op ration of a first class oc rating mill for dry concentrators 1 ae axen tried again and again 1 nt all 1 av will out exception faircl As MILI MAN I 1 ark city dec 21 1896 |