Feb. 2, 1920.] Agricultural Gazette of N.S.W. 91 



French Potash-salts* 



F. B. GUTHRIE. 



The first consignment of potash-manure from Alsace has recently been 

 landed and is now available for farmers. It is consequently an opportune 

 time to say a word or two concerning this product, especially as some mis- 

 conception exists as to its value as a fertiliser. 



Hitherto, or before the war, the supplies of potash manures imported into 

 this country, and indeed into nearly every other country, were obtained 

 from the Stassfurt deposits in Germany. A considerable variety of potash 

 salts was derived from these enormous mines, of which kainit, sulphate of 

 potash, and muriate of potash were the principal. As far as we were concerned 

 locally, the importations of recent years were almost exclusively confined to 

 sulphate of potash, kainit (the lower grade) being relatively more expensive, 

 and the sulphate being more readily obtainable and cheaper than the muriate. 

 Probably this latter state of things was merely a trade convenience, since the 

 muriate is the principal potash -salt used as a fertiliser in Great Britain and 

 the United States, and perhaps in some other countries. It appears to be 

 not unlikely that the shipping of sulphate of potash to Australia was 

 encouraged in order to find a convenient market for it. The position now is, 

 that having been without potash-salts for the past five years, the require- 

 ments in this direction are being met by importations of potash manures 

 from Alsace. 



The salts obtainable from this source are sylvinite and muriate of jjotash. 

 Muriate of potash is the trade name for potassium chloride, sylvinite being 

 potassium chloride mixed with other salts which are removed in the pre- 

 paration of the muriate. As muriate of potash is the name under which it 

 will apparently be most familiar, that name will be adhered to in these notes. 



Sylvinite is the raw product of the mines and is obtained in two grades, 

 one containing 14 per cent, potash, known as French kainit, and the other 

 containing 20 per cent, potash and known as French manure salts. 



Muriate of potash is the above crude salt purified until it is nearly pure 

 muriate of potash, containing 50 to 60 per cent, potash. It is this latter salt 

 which constitutes the present consignment, and which will probably be in 

 the future, or at least for a considerable time, the only potash salt available 

 to the farmers of this country. 



This muriate is sold in two grades — A, containing 52 per cent, potash, and 

 M, containing 58| per cent, potash. Grade A contains practically identically 

 the same percentage of potash as the sulphate, and can replace it in maniire- 

 formulsB, weight for weight. 



It is important to bear in mind that the whole difference between the 

 present supply and the product with which we had previously to deal, is that 



