CHAPTER III. 



CHEMICAL PROPERTIES OF CLAY. 



CONTENTS. 



Introductory. 

 Minerals found in clay. 

 Quartz. 

 Feldspar. 

 Mica. 

 Iron ores. 

 Pyrite. 

 Glauconite. 

 Kaolinite. 

 Rutile. 

 Calcite. 

 Gypsum. 



Hornblende and garnet. 

 Dolomite. 

 Chemical analysis of clays. 



Method of ultimate analysis. 

 Rational analysis. 

 Compounds in clay and their effect. 

 Silica. 

 Iron oxide. 



Sources of iron oxide in clays. 



Effects of iron compounds. 



Coloring action on raw clay. 



Coloring action on burned clay. 



Fluxing action of iron oxide. 



Effect on absorptive power and shrinkage. 

 Lime. 



Effect of lime carbonate on clay. 



Effect of lime-bearing silicates. 



Effect of gypsum. 

 Magnesia. 

 Alkalies. 

 Titanium. 

 Water. 



Mechanically combined water. 



Chemically combined water. 



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