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Utilization of Indiana Kaolin. 



William N. Logan — Indiana University. 



Extensive beds of kaolin exist in Lawrence and Martin counties in 

 the horizon of the Huron formation. The kaolin has been mined and 

 utilized to a limited extent only. Its abundance and quality justifies a 

 more extended use. Attempts have been made to use it as a substitute 

 for southern kaolin used in Indiana in the manufacture of encaustic 

 tile. The lack of bonding power is evident from the cracks and crazes 

 which occur in the burned ware. The writer undertook to find a clay 

 which might be mixed with the kaolin for the purpose of supplying 

 bonding power and tensile strength. Mixtures of pottery clays and 

 Indiana fire clays were made and the objects burned. It was found 

 that tile could be manufactured successfully out of the kaolin when 

 from 25 to 40 per cent of fire clay was added. 



