The Metallurgy of Lead & Silver: LeadGriffin, 1899 - Lead |
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Page 3
... take simultaneously two perfectly independent duplicate samples . Hand Sampling . - Instead of requiring all the parcel of ore to be crushed moderately fine at once , the system of hand sampling admits of a gradual reduction in size by ...
... take simultaneously two perfectly independent duplicate samples . Hand Sampling . - Instead of requiring all the parcel of ore to be crushed moderately fine at once , the system of hand sampling admits of a gradual reduction in size by ...
Page 4
... takes the form of a flat circular cake from 6 to 15 feet diameter and from 6 to 12 inches thick . The cake is then cut into four quarters ( whence the name " quartering " ) by means of a straight - edge , or merely by marking its ...
... takes the form of a flat circular cake from 6 to 15 feet diameter and from 6 to 12 inches thick . The cake is then cut into four quarters ( whence the name " quartering " ) by means of a straight - edge , or merely by marking its ...
Page 7
... take about five minutes ) , the contents of the crucible are stirred and its sides scraped down with a chisel- ended iron rod . The crucible is returned to the furnace for a few minutes , again removed , the sides again scraped down and ...
... take about five minutes ) , the contents of the crucible are stirred and its sides scraped down with a chisel- ended iron rod . The crucible is returned to the furnace for a few minutes , again removed , the sides again scraped down and ...
Page 8
... takes from fifteen to twenty minutes if the heat be right , or may take thirty minutes if the temperature be too low . As soon as tranquil fusion is obtained the crucible is withdrawn , and the nails removed one by one with a pair of ...
... takes from fifteen to twenty minutes if the heat be right , or may take thirty minutes if the temperature be too low . As soon as tranquil fusion is obtained the crucible is withdrawn , and the nails removed one by one with a pair of ...
Page 9
... Take 1 gramme of ore , dissolve in a 250 c.c. flask with 10 c.c. con- centrated HNO , and a few drops of HCl , boil ... takes from thirty to forty minutes , and the results are accurate , though subject to a plus error of from 0.1 to ...
... Take 1 gramme of ore , dissolve in a 250 c.c. flask with 10 c.c. con- centrated HNO , and a few drops of HCl , boil ... takes from thirty to forty minutes , and the results are accurate , though subject to a plus error of from 0.1 to ...
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alloy amount antimony arsenic assay average blast furnace bottom brick Broken Hill bullion carbon cast-iron cent charge CHARLES GRIFFIN coal coke concentrates consumption containing cooling copper cost crucible crust cupellation desilverisation doors dross dust Engineers EXETER STREET feet firebrick Flintshire flue flue-dust flux Freiberg fuel fume fusible fusion galena gases gold grey slag hearth Hofman inches iron jackets labour Lautenthal lead and silver lead sulphide Leadville lime liquation litharge matte melting metal Metallurgy Metallurgy of Lead method mixture molten oxide oxidised Parkes process pipe plates Port Pirie practice produced proportion pyrites quantity rabble reaction reduced residues reverberatory reverberatory furnace roasting sample Schnabel scorifier separate shown in Figs silicates silver contents sintering SiO2 skimmings slag smelting softening furnace speiss sulphate sulphide Table tapped temperature tons Trans treated tuyeres volatilisation volatilisation loss weight work-lead zinc
Popular passages
Page 85 - The arguments for and against " sintering " and " slagging " respectively have been already stated in this chapter, and need not be repeated here. Suffice it to say that the...