12 JOURNAL OF THE 



case of so many h3^droxides precipitated by alkaline hy- 

 droxides, merely a stubborn retention of alkali. Assum- 

 ing- that the strong- alkaline solutions held zirconates in 

 solution, attempts were next made to prepare other zir- 

 conates by precipitation from them. 



The addition of solutions of various salts g-ave small 

 precipitates which seemed to be formed mainly because 

 of the dilution of the alkaline hydroxide and to consist 

 almost entirely of zirconium hydroxide. It was neces- 

 sary, therefore, to use strong^ly alkaline solutions of the 

 compounds of the elements to be experimented with. 

 This ^rreatly diminished the choice of compounds. Con- 

 centrated solutions of aluminum and zinc hydroxides in 

 potassium hydroxide g-ave precipitates but they were in 

 too small amounts for reliable analyses to be made. 



Summing- up the results of the experiments performed, 

 it is clear that the method yielding- the best results for 

 the preparation of the zirconates is fusion of g-ently dried 

 zirconia with hydroxides or prolong-ed heating- with the 

 oxides. In the case of the alkaline earths this yields zir- 

 conates containing- one equivalent of each oxide, CaO.ZrOg, 

 etc. The same is true of the mag-nesium compound. 

 For lithium the compound obtained was LiOZrOg. For 

 the alkalies it seemed to be possible to obtain only zircon- 

 ates having a largely preponderating- proportion of zir- 

 conia. There seems to be a tendency toward the forma- 

 tion of distinct compounds under certain conditions. 

 These polyzirconates, and the. lithium compound also, 

 may be decomposition products due to the action of the 

 water used in leaching-. No other mode of separation 

 from the products of the fusion could be devised by us, 

 however, If they are produced by the decomposing- and 

 solvent action of water, it is a little strang-e that a point 

 should be reached beyond which the leaching- extracted 

 no more alkali, and that this point varied with chang-ed 

 conditions. This is not the case where zirconium hy- 

 droxide has been precipitated by an alkali. 



