116 



CEMENTS, LIMES, AND PLASTERS. 



than the high-calcium limes, and will therefore carry much more sand. 

 This fact is brought out, for one instance, by the tests given on p. 122. 



Composition of commercial high-calcium limes. The non-mag- 

 nesian or high-calcium limes as marketed will rarely carry less than 

 90 per cent of lime oxide (CaO), while they commonly carry over 95 

 per cent. The remaining 5 or 10 per cent is made up of magnesia 

 MgO), silica (SiO 2 ), alumina (A1 2 3 ), iron oxide (Fe 2 3 ), and a little 

 carbon dioxide and water. In the following table a number of analyses 

 of representative high-calcium limes are given. 



TABLE 38. 

 ANALYSES OF HIGH-CALCIUM LIMES (U. S.). 



* For references see next page. 



