222 The Potash Deposits of Germany. [july, 



The natural salts consist of kainit, hartsalz, sylvinit, carnallit,, 

 and kieserit. Of these kainit is the most important for agricultural 

 purposes. 



According to a handbook (" Die Kalisalze ") recently issued by 

 the German Agricultural Society, the average composition of 

 each of these salts is as follows : — 





Kainit. 



Plartsalz. 



Sylvinit. 



Carnallit. 



Berg- 

 kieserit. 





Per cent. 



Per cent. 



Per cent. 



Per cent. 



Per cent. 



Potassium Sulphate (K.^SOj) 



21 '3 





1-5 







Potassium Chloride (KCl) ... 



2'0 



2173 



26-3 



I5'5 



11-8 



Magnesium Sulphate(MgS04) 



I4'5 



26-95 



2-4 



I2-I 



21-5 



Magnesium Chloride (MgCl.,) 



12-4 



171 



2-6 



21'5 



I7'2 



Sodium Chloride (NaCl) .". 



34-6 



38-52 



567 



22 4 



267 



Calcium Sulphate (CaS04)... 



17 





2-8 



1-9 



•8 



Matter insoluble in water ... 



•8 



5-67 



3'2 



•5 



1*3 



Water ... 



127 



4-97 



4-5 



26-1 



207 



Kainit. — In a pure state, kainit is composed of sulphate of 

 potash, sulphate of magnesia, chloride of magnesia, and water, 

 but. in its natural condition, as obtained from the mine, it always 

 contains in addition a quantity of common salt (sodium chloride). 

 Kainit is sometimes spoken of as a sulphate of potash and 

 magnesia, but this is not quite correct, as it contains in addition 

 chloride of magnesia, a small quantity of chloride of potash, as 

 well as 35 per cent, of chloride of sodium, so that the chlorides 

 amount altogether to 49 per cent. This is less than that in 

 carnallit, but it is sufficient to suggest caution in applying it in 

 those cases where chlorides are likely to be injurious. Kainit 

 hardens into lumps when stored, particularly in damp places, sq 

 that it cannot easily be distributed, and in order to prevent this 

 mixing with 2\ per cent, of dry earth or peat is recommended 

 where it is not intended for immediate use. Kainit is usually 

 guaranteed to contain I2'4 per cent, of pure potash. 



Among the other natural potash salts are : — 



Hartsalz.— salt is rich in chlorides, of which it contains 

 62 per cent. Its potash content is not less than I2"4 per cent.^ 

 so that as a manure it is similar to kainit. 



Sylvinit. — This potash salt contains 85*6 percent, of chlorides, 

 and has on the average 17*4 per cent, of potash, though 

 only guaranteed to contain 12*4 per cent. 



Carnallit, — This is principally employed for trade purpose? 



