Clarice and Steiger — Action of Ammonium Chloride. 37 



leuchtenbergite, and phlogopite, and the remainders of the 

 original samples were fortunately at our disposal. The 

 analyses made by Schneider are, therefore, directly comparable 

 with the new data secured by us. 



The serpentine, from Newburyport, Massachusetts, was but 

 moderately attacked upon heating with ammonium chloride. 

 Upon leaching the contents of the sealed tube with water, 0*1 8 

 per cent of silica and 5*23 of magnesia went into solution. 

 The washed residue and the serpentine had the following com- 

 position. 



Serpentine (Schneider). Residue (Steiger). 



SiO„ ._. 41-47 45*42 



Fe 2 3 ,Al,0 3 _.. 1-73 -88 



M£>0___. 41-70 39-54 



FeO -09 



KH 3 _.. -09 



HO 15-06 14-01 



100-05 99-94 



The leached residue contained 1*06 per cent of soluble silica. 

 The amount of change effected in the mineral was evidently 

 small, and no ammonium compound was produced. 



Leuchtenbergite. 



From the standard locality near Slatoust in the Urals. 

 When the contents of the sealed tube were leached with water, 

 there passed into solution 0*19 per cent of alumina, plus iron, 

 2*10 of magnesia, and 2*03 of lime. The residue was not com- 

 pletely analyzed, but the few determinations made contrast 

 with Schneider's results as follows : 



Leuchtenbergite. Residue (Steiger). 



Si0 2 32-27 32-82 



A1 2 3 16-05 



Fe 2 3 4-26 



FeO .... -28 



MgO ". 29-75 



CaO 6-21 l 4-67 



NH 3 .... -25 



H 2 11-47 12-11 



100-29 



No definite ammonium compound was formed, and the amount 

 of decomposition was small. As the lime shown by the analysis 

 is at least partly due to the presence of garnet as an impurity 

 in the mineral, it will be interesting to determine the effect 

 producible by ammonium chloride upon that species. 



