494 AGRICULTURAL ANALYSIS 



of them contain from 20 to 30 per cent, actual potash, but in 

 most cases in such combination as not to pay for the necessarily 

 expensive extraction. Because of this comparatively large con- 

 tent of potash, however, they are dried, calcined, pulverized, and 

 mixed with crude salts, or other poorer forms of potash, to in- 

 crease the potash content of these salts and give them added 

 value for agricultural purposes. 



Besides the agricultural use of potash salts, large quantities 

 are consumed by the chemical industry in Germany, the United 

 States and other countries, in the manufacture of caustic potash, 

 carbonate, nitrate, chlorate, chromate, bichromate, alum, cyanid, 

 bromid, permanganate and yellow prussiate of potash and of other 

 compounds. 



COMPOSITION OF CRUDE SALTS (NATURAL PRODUCTS). 



Kainit. Carnallit. Sylvinit. 

 Per cent. Per cent. Per cent. 



Actual Potash (K 2 O) 12.8 9.8 17.4 



Minimum Guarantee (K 2 O) 12.4 9.0 12.4 



Sulfate of Potash (K 2 SOJ 21.3 1.5 



Muriate of Potash (KC1) 2.0 15.5 26.3 



Sulfate of Magnesia (MgSOJ 14.5 12.1 2.4 



Chlorid of Magnesia (MgClj) 12.4 21.5 2.6 



Chlorid of Sodium (NaCl) 34-6 22.4 56.7 



Sulfate of Lime (CaSO 4 ) 1.7 1.9 2.8 



Insoluble Substances 0.8 0.5 3.2 



Water 12.7 26.1 4.5 



SULFATES (NEARLY FREE OF CHLORIDS). 



Sulfate of Potash. 



Sulfate 



90 96 of Potash 



per cent. per cent. Magnesia. 



Actual Potash (K,O) 49-9 52-7 27.2 



Minimum Guarantee (K,O) 48.6 51.8 25.9 



Sulfateof Potash (K,SO<) 90.6 97.2 50.4 



Muriate of Potash (KC1) 1.6 0.3 



Sulfate of Magnesia (MgSO 4 ) 2.7 0.7 34.0 



Chlorid of Magnesia (MgCl,) i.o 0.4 



Chlorid of Sodium (NaCl) 1.2 0.2 2.5 



Sulfate of Lime (CaSO 4 ) 0.4 0.3 0.9 



Insoluble Substances 0.3 0.2 0.6 



Water 2.2 0.7 n.6 



