CHINA CLAYS. 125 



Analysis of China Clay, fureka Mines, DeKalb Co. 



Silica 5 53.7300 



Alumina 34.5390 



Ferrous oxide .8530 



Lime 4144 



Magnesia ' 3420 



Alkalies tr 



Sulphuric acid 2018 



Phosphoric acid 0522 



Ignition 12.28 



102.4124 

 Total fluxes 1.609 



The following analysis of sample collected by writ- 

 er from the mines in 1897, gave the following : 



Analysis of China Clay, Eureka Mines, DeKalb Co. (No. 128.) 



Silica 82.11 



Alumina 11.41 



Ferric oxide 1.40 



Lime tr 



Magnesia 661 



Alkalies '. 1.80 



Ignition 4.001 



4.001 



101.382 

 Total fluxes . 3.86 



The rational analysis gave. 



Clay substance 20.20 



Quartz 69.20 



Feldspar . 10.40 



99.80 



The feldspar percentage influences the fusibility of 

 this clay, and the difference in the two quantitative 

 analyses is due to the latter having been made on an 

 unwashed sample. 



