Show importance OF TUNGSTEN 44 georg mining american of h e word tungsten is swedish and n at ci s heavy stone a very apt title for a alid whose identity remained a mystery juthe tile latter iatter part of the eighteenth cen than angsten ung sien is a word of almost magic I 1 t wid d it means as much to tile the miner of oppe as ab did gold to the forty biners A perty ayears ears ago it was execrated by the gold henrs of boulder county colorado and crapo la avoided voided whenever possible because it liel tile the value of their concentrates in r respect its history resembles that of bence f 0 ther other metals in the great comstock 0 of nevada where the early miners cikity w away the black sulphide of silver amma m t several thousand dollars per ton and M wil leadville while the camp was getting its re hedsand Hel 11 vand narl Sand the lead carbonates caused the w 1 alper per miners a great deal of trouble by ng up the riff fiffles riffles les in the sluice boxes and 44 r pr fering with tile the saving of the gold made millions for the comstock min omaz lead carbonates with their contents did mr same for leadville and tungsten bids re r to do likewise for its producers rues the he principal minerals of tungsten are ida Q abai ee lite and hubner aiace some of the finely ground ore in a tall mcelain Hc elain celain dish or test tube with a mixture it ilour parts of hydrochloric acid and one 3 amt nitric acid and boll boil twenty minutes ca there is tungsten present the yellow e kader of tungsten trioxide will appear and i pi adding a piece of tin or zinc and heat aon the solution will turn blue acor mix some of the finely ground ore th ten times its volume of sodium carbon of Q common cooking soda and heat strong enrin an iron spoon or crucible until thor t ehly fused crush the fused mass boil wrongly angly in a small quantity of water until ill dissolved and filter divide the men into two equal parts adding concentrate hydrochloric acid in excess to both boil er of a 3 first portion a few minutes and add zinc tin A blue color which with continued ailing turns to brown indicates tungsten f til il the second part for several minutes aa a yellow powder appears filter and wash e residue with water add strong am onia to it and if the yellow powder be it is tungsten trioxide w if tungsten is still suspected of being in of e ore but is not indicated by the above cpr ats crush a larger quantity of the ore to kl fine state concentrate by panning and malarly test the concentrate ra re insoluble in all the metal is practically ole le common salts its melting point is 3 17 degrees C the highest of the known er petals atals it is not affected by the atmosphere of s tensile strength exceeds that of iron or ckel and it is so ductile that it can be ofrain rawn to smaller size wires than can any lather known metal at the same time retain ing its remarkable strength and pliability its largest uses at present are in tool steel lining high powered guns and cannons hardening armor plate and the points of armor piercing shells it is said that one metal cutting machine equipped with tung sten steel can do the work of five machines equipped with carbon steel tools As a steel alloy tungsten is added in varying quantities for saw blades 1 per cent to 2 per cent for high speed tools used in working metals from 16 to 20 per cent tung sten steel drills by holding their temper when red hot can be run at many times greater speed than carbon steel drills and therefore their use results in a large saving of labor costs tungsten steel is self hardening |