Canadian Spessartite and Mountain Cork. 227 



The atomic and quantivalent ratios deduced from the 

 above figures are: — 



Atomic. Quantivalent. 



Si ... 605 x 4 = 2420 2420 2420 1 



Al... 378 x 3 = 1134 1134 -i 



Fe" . . 148 x 2 = 296 1 ! 2408 1 



Mn .. 423 x 2 = 846 1 , 97zL f 



Ca... 55 x 2 = 110 ( 1274J 



Mg... 11 x 2 = 22 J 



The analysis shows that the mineral is a manganese 

 garnet, approaching very nearly in composition to the 

 original spessartite, but containing more lime. The iron 

 was proved to be all in the ferrous state. The figures given 

 as loss on ignition indicate the loss on heating for about 

 fifteen minutes. Further heating caused a gain in weight, 

 owing to oxidation of the iron. 



2. — Mountain Cork. 



In 1 STY, the writer found on the dump at the "Grant 

 Phosphate Mine," in the township of Buckingham (south J 

 of lot 18, Range 12), specimens consisting of mountain 

 cork and mountain leather. Under the latter name they 

 were referred to in his " .Report on the Minerals of some of 

 -the Apatite-bearing Veins of Ottawa County," but were not 

 then analysed quantitatively. During the past few years, 

 in the Emerald Mine, on the same lot as the above, similar 

 material has been obtained in masses of considerable size, 

 one specimen presented to the Peter Redpath Museum by 

 Mr. F. W. Warwick, containing about half a cubic foot. 



It consists mainly of mountain cork, though on the 

 surface it is in places slightly foliated or leather like. Some 

 portions contain irregular grains of quartz and minute 

 crystals of copper pyrites 1 ; but fragments were selected for 



1 The crystals are mostly 1 to 2 mm. in diameter and many of 

 them black superficially. When freshly fractured they have the 

 colour of copper pyrites, with which they also agree in blowpipe 

 characters. To the eye the crystals look like regular octahedrons 

 but may be tetragonal. They require further examination. 



