MINERAL DEPOSITS OF FERTILIZERS 41 



are easier to work than some of the German deposits. The 

 percentage of potash is also satisfactorily high. Under 

 French control the Alsace-Lorraine deposits are yielding 

 kainite and sylvinite containing 14 % of pure potash, 

 potash manure salts containing 20 % of pure potash and 

 muriate of potash containing 50 % to 60 % of pure potash. 



Other European Deposits. Galicia contains some 

 small beds not used for export. Some Spanish deposits 

 at Suria, in Catalonia, have recently been discovered in 

 districts where rock-salt mines are already working. For 

 some time German control succeeded in checking the 

 development of these deposits, but there is considerable 

 hope that they will now be pushed ahead. Carnallite and 

 sylvinite are both common in the Spanish deposits. Some 

 of these newer workings are carried down to a depth of 

 800 metres. Probably these Spanish deposits extend over 

 a large area. 



In addition there are the Italian deposits at Erythrea, 

 which are of recent lake formation. The reserves are not 

 very large, but they are extremely rich, some samples 

 containing as much as 80 % of potassium chloride. 



United States Deposits. The United States deposits 

 are salt lakes situated in the Rocky Mountains. The lake 

 Series, in California, yields liquors which by concentration 

 and crystallization produce potash salts. 



African Deposits. In Tunis there is a salt lake which 

 yields potash and bromine. 



Other Sources. In Chili, in the province of Tarapaca, 

 there are lakes which contain deposits of potassium chloride 

 varying from 3 % to 30 %. Potash, in the form of potassium 

 nitrate, in India has already been alluded to on p. 25. 

 Most of the potash deposits described above have been 

 originally formed in Nature by the evaporation of sea 

 water. When sea water is evaporated, it first deposits 

 sodium chloride and then magnesium salts separate out. 

 This process can be carried out artificially as well as under 

 natural conditions ; the employment of fuel, is, of course, 

 out of the question, but sun heat can be utilized under 



