310 CHEMICAL MANUEES. 



Commercial Brands of Potassium Chloride {Muriate of Potash). 

 — The principal commercial brands of potassium chloride supplied 

 by the Stassfurt factories are the following : — 



(a) 70 to 75 per cent potassium chloride (muriate of potash) 

 containing on an average 45 per cent of pure potash (K.^0) and 

 21 per cent of sodium chloride, 2*5 per cent of water, 1-7 per cent 

 of sulphate of potash, 0*8 per cent of sulphate of magnesia. 



(b) 80 to 85 per cent potassium chloride (muriate of potash) 

 containing on an average 50 per cent of pure potash (K^,0), 14 per 

 cent of sodium chloride and 1*1 of water, etc. 



(c) 90 to 95 per cent potassium chloride (muriate of potash) 

 containing 56*9 per cent of pure potash (K.p), 7 per cent of sodium 

 chloride and 0*6 per cent of w^ater. 



(d) 97 to 98 per cent of potassium chloride. It is the most 

 concentrated product. For this latter certain factories guarantee 

 0"5 per cent of sodium chloride, for which an extra charge is made. 



The selling price for all sorts is based on 100 kg. (220 lb.) at 

 80 per cent, bags included, that is to say that products with a plus 

 value are brought to 80 per cent by calculation. An example will 

 make this custom more plain. Suppose that the price of potassium 

 chloride of 80 per cent be 9 '40 francs, bags included, say 3s. 9d. the 

 cwt. If the muriate bought is of a higher strength (say 95 per 

 cent) it will cost 11-14 francs (say 4s. 6d. the cwt.), that is to say 

 100 kg. (220 lb.) of muriate at 95 per cent strength correspond to 

 118-75 kg. (261-25 lb.) of 80 per cent muriate. It is clear that 

 the price increases proportionately with the purity of the muriate. 



As to sulphate of potash the price is calculated on a 90 per cent 

 basis. Consequently 100 kg. (220 lb.) of this product at 95 per 

 cent equal 110 kg. (242 lb.) at 90 per cent. Sulphate of potash 

 of a guaranteed strength of 96 per cent is worth about 0-50 francs 

 (4'8d.) more per 110 kg. (220 lb.) or 2^d. more per cwt. (price 

 based on this basis is price of 90 per cent) than the sulphate which 

 only tests 90 per cent. 



Remarks on the use of Potash Salts as Fertilizers. — As already 

 seen, the Stassfurt mines furnish crude salts and refined salts as 

 fertilizers. Which should be preferably used ? This question is of 

 great practical importance which farmers are far from doubting if 

 we are to believe the emphatic putfs of kainit dealers and the other 

 societies " for the encouragement " (so-called) of the diffusion of 

 manures. In the last thirty years the consumption of potassic 

 manures has progressed considerably, but instead of using pure 

 salts the farmer has chiefly used the crude salts, kainit and carnal- 

 lite. As will be seen in the analyses given below, crude potash 

 salts contain besides potash, sodium chloride, magnesium chloride, 

 etc. ; in fact they contain much more chlorine than potash. 



