COLLECTIONS IN ECONOMIC GEOLOGY AND METALLURGY. 51 



contain a valuable amount of metals. They are recharged into the 



blast furnace: 



Stoney (51327.) 



Per cent. 



Silica (SiOo) 33. '27 



Protoxide of iron (FeO) 37.76 



Protoxide of manganese (MnO) 1.42 



Ahuniua (AI2O3) 4.46 



Oxide of zinc (ZnO) 4.02 



Lime (CaO) 14.24 



Magnesia (MgO) trace 



Oxide of lead (PbO) 1,46 



Sulphur (S) 2.04 



Cryslallized {blA28.) 



Per cent. 



Silica (SiOs) 31. k; 



Protoxide of iron (FeO) 31.34 



Protoxide of manganese (MnO) 1. 37 



Alumina (AljO.O 4. 15 



Ozide of zinc (ZnO) 1 9. 01 



Lime (CaO) 18.66 



Magnesia (MgO) trace 



Oxide of lead (PbO) 1.83 



Sulphur (S) 1.39 



Crystallized (51329.) 



Per cent. 



Silica (SiOj) 32.13 



Protoxide of iron (FeO) 32. 03 



Protoxide of manganese (MnO) 1.27 



Alumina (AI2O3) 4. 13 



Oxide of zinc (ZnO) 9.23 



Lime (CaO) 18.86 



Magnesia (MgO) trace 



Oxide of lead (PbO) 2.35 



Copper (Cu) trace 



Sulphur (S) 1.43 



-Sfo/iev (51330.) 



Per cent. 



Silica (SiO,) 30.34 



Protoxide of iron (FeO) 32. 13 



Protoxide of manganese (MnO) 1. 32 



Alumina (Al:Oj) 3. 80 



Oxide of zinc (ZnO) 6.44 



Lime (CaO) 22. 72 



Oxide of lead (P1)0) 1*40 



Sulphur (S) ,. , 1.39 



Sfonei/ (51,331.) 



Per cent. 

 Silica (SiO.) 31.79 



Protoxide of iron (FeO) 31. 77 



Protoxide of manganese (Mn(^ ) 3. 05 



Alumina (AljOa) (j.50 



Oxide of zinc (ZnO) 6.72 



Lime (CaO) 1,5,58 



