XXII GEOLOGY AND MINING INDUSTRY OF LEADVILLE. 



Page. 

 Tables of analyses and notes on methods employed Continued. 



Ores and vein materials Continued. 



Table X. Various ores, vein materials, and country rocks 602 



Table XI. Alteration products of porphyry (kaolin and Chinese talc) 603 



Table XII. Alteration products of galena and pyrite (basic sulphates) 606 



Table XIII. Miscellaneous alteration products 607 



Table XIV. Assays of ores, vein materials, and country rocks 608 



APPENDIX C, BY ANTONY GCYARD. 

 METALLURGY. 



INTRODUCTION 613 



SKCTION I. 



PRELIMINARY CONDITIONS OF SMELTING 614 



Leadvillo Its situation C14 



Location and output of its mines, Table I 615 



Ores Description of chi<-f ores Analyses of carbonate, chloride, and average ores Assays 



of ores from principal mines, Table II 616 



Smelting works Their location, cost of plant, Table III, and general arrangement 625 



Ore buying Its method 627 



. Sampling and sampling works 628 



Crushing and crushers used 629 



Assaying Apparatus and methods 632 



SECTION II. 



MATERIALS USED IN SMELTING 036 



General considerations 636 



Statistics of Leadville smelters, Table IV C37 



Construction materials 641 



Fuels and flaxes 641 



Coke Analyses VII anil IX 641 



Charcoal 642 



Dolomites Analyses X to XIX 643 



Limestone Analysis XX 646 



Hematite Analysis XXI li-lfi 



Ore beds Their composition, Table V 648 



Smelting charges at individual smelters 649 



Resume" and general discussion of smelting charges 659 



SECTION III. 



PLANT AND SMELTING OPERATIONS 659 



Smelting plant in general Furnaces and blast apparatus. Table VI 659 



Smelting operations in general Drying, blowing-in, charging, barring-down, smelting of 

 dusts, tapping of clay, matte and speiss, ladling-out of bullion, watching and blow- 

 ing-out ^ 664 



Cost and profits of smelting 668 



Plant and operations of individual smelters G69 



SECTION IV. 



PRODUCTS OF SMELTING 692 



Bullion Its sale Shipment, Table VII Analyses and assays Skimmings Losses Bull- 

 ion capacity of smelters, Table VIII Bullion production, Table IX 692 



