1880.] 



NATURAL SCIENCES OF PHILADELPHIA. 



sn 



is h^'groscopic, and may be driven off eitlier by long exposure over 

 sulphuric acid in a desiccator, or by drying in an air-bath at 100° 

 C. The percentage of water given in the analj'ses represents 

 approximately the amount of water in the mineral after such 

 desiccation. 



Spec. grav. (taken in alcohol of 95 p. c.) 2.78-2.96. 



SiO, 



Al,,03 



Fe.,03 



Fe^O 



MnO 



MgO 



CaO 



Na,0 



Li.b 



K2O 



F 



H2O 



H^-gr 

 Spec. 

 2.80. 



SiO,, 

 TiO,, 



Ai,d, 



Fe^Og 



V2O3 



FeO 



MnO 



NiO| 



CoO) 



CuO 



MgO 



CaO 



Xa,0 



Li.,0 



K.2O 



PO, 



CI 



H,S04 



H,0 



I. 



39.06 

 14.75 

 20.59 

 2.04 

 trace 

 11.49 

 .99 

 .90 

 trace 

 6.89 

 trace 

 4.27 



II. 



38.52 

 14.82 

 20.01 

 2.04 

 trace 

 11.32 

 1.08 

 .64 

 trace 

 6.61 

 trace 

 4.27 



Mean. 



38.79 



14.78 



20.30 



2.04 



11.40 

 1.03 



.77 



6.75 

 4.27 



Quantivalent ratio. 



2.587 

 .861 

 .761 

 .056 



.570 

 .037 

 .025 



.143 



.474 



2.587 

 1.622 



5.45 

 3.42 



.831 



1.75 



.474 1.— 



100.98 99.31 100.13 

 oscopic water in I, 3 12 ; in II, 3.43. 

 grav. (taken in alcohol of 84 p. c on the air-dried mineral) 



III. 



35.94 



1.30 



15.23 



19.48 



.37 



2.09 



.46 



trace 



trace 

 11.41 

 1.38 

 1.42 

 trace 

 6.52 

 trace 

 trace 

 trace 

 4.34 



lY. 



35.52 



.77 



16.32 



19.43 



.36 



2.28 



.55 



.06 



.08 



11.72 



1.54 



.38 

 ti'ace 

 7.11 



.11 

 trace 

 trace 

 4.34 



Mean. 



35.73 



1.03 



15.77 



19.46 



.37 



2.18 



.50 



.06 



.08 



11.56 



1.46 



.90 



6.81 

 .11 



4.34 



2.43 



5.05 



Quantivalent ratio. 

 2.38 

 .05 

 .91 ) 



.73 V 1.65 3.43 

 .01 ) 

 .06 ^ 

 .01 



5 



3 



.58 

 .05 

 .03 



.14 



.87 



1.80 



.48 



.48 1 1 



99.94 100.63 100.45 

 Hygroscopic water in III and IV, 3.24. 



