Arizona silver belt., 1899-10-19
CONCENTRA ATES.
Items of Interest in Regard to Mines
 and Timing.
From Mining and Scieutinc Press. 1


 process.
 Carburundlm is a competitor Of emery in all the uses of that abrasive, and is produced in large quantities at Niagara Falls, N. Y.
 The De Beers diamond mine, in South Africa, is considered to be the largest mining dividend payer in the world: if paid last year s7.6SI,09
 Supcrheated steam is that which is further raised by the application of additional heat t0a temperature above that which belongs to its equilibrium of temperature and pressure when in contact with its liquid.
 Machine drills do not work to ad- vantage in soft ground. The bits cut rapidly but quickly churn the soft material into thick paste that is pounded into the bottom of the hole, retarding the operation of the drill,
 Blankets were at enc time much in use for the purpose of concentrating sulphideS from tailingS but they have in recent years been replaced by cheap brussels carpet orstillmore commonly hy canvas of various grades.
 When required assessment work on an unpatented mining claim has been actually done, and can be definitely proved by responsible witnesses, no one can legally jump that claim. IT. is, however, safer to record the work,
 Sea water is successfully emploNe'l in extracting gold by means of th'' cyanide process. in Chile. The tnt. gold found in some beach sands coult. probably be extracted in the same manner. IL Is q material we'll suited to teaching.
 in some of the Central American countries the native miners strike single handed using lppound ham mer having q handle IS inches ir length. The blows fall slowly, but in time they put q hole down. Theycon- slider 3i-pound hammer q toy.
 Magnetic is magnetic iron ore. usually occurring in octahedronS. also in dudecahedr0nS, often granular: sometimes found in detritic form be- tween sheets of mica forming peculiar and interesting figures. hnt destroy ing the mica fpr commercial uses.
 Wolframite is the technical term for tungStalc of iron. IIuhncrite is the term for tungStajc of manganese, both of which are found in the yicin' ity nf Gladstone, tolo. Stolgite, tung- state of lead. k believed to exist in the Red mountain. Colorado, ores.
 In many of the guld-beariug veins uf southern California. Arizona and southern Nevada mulybdare uf lead occurs in small quantity and is often mistaken for gold by inexperienced propectorS. when banning the crushed ore. Itwill completely decampo>ed hy hydrUchlorir acid,
 American mining machinery k se- curing worldwide recognition on lts merits. In south America. S0uil Africa. Australia. Russia. Japan. etc. the most advanced mine managers regardless of nationality. Stipulatc that mining machinery Of American manufacture shall b. used.
 A vendor who brings principals to gether is in general considered to he entitled to commission, whether busi' ness is done direct. or through him. Such matters are. however, determ. ined largely by special agreement, which. in q ease of any consequence. should be in writing So worded that Che intent cannot bc misunderstood
 Prupolitc iS rock which has been re- cogniZcd as q distinct species by sev- eral writers of note. among them Iir kel and Stachc Later microscopic investigation has resulted in the gen eral opinion that propyite is altered hOrnblcndc andesitc. in which the hornblendc material has penetrated the fcldsparS during the process ot all teration. and lhc hornblcndc crystal' are found altered to chlnril" and cpl tlutc. These rucks contain quartz auc are found without it.
 Cunglumcrate iS q nass uf gravel sand and cobblcS. all more or lcs' rounded by attrition on q lake or sc; shore or in river bed and cemcntet by some material. such aS lime ir0I oxide. silica. etc. Brcccia is q mass e material similarly ccmcnted. bu, th' fragments are all angular. II may h the result of q volcanic eruption Q may br rock in situ which has lecl fractured by dynamic forces and sub sequcntly crmcnted. Either may con tain ores and valuable metals
 lThc drying of ores by calcining prc yiuus.lo ary crushing often does nor harm than good. particularly wher the ores contain much >ulphide min pral us inc uartial oxidation of tn