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possible this name may be a})i)lied to many of our local fekls[)ars, bnt 

 until analysis shall have established their jtroperties it will be better to 

 refer to them under the general heading of feldspar. 



Orthoclase. — The gneissic and granitic rocks, so extensively de- 

 veloped in these townships, consist for the most part of various colored 

 feldspars, associated with qiuwtz, mica, hornblende, ikc. Tne strong 

 structural resemblance of the various members of the feld.s})ar family 

 makes it difficult to discriminate between the several allied minerals. 

 Neither do I think it possible (except in well crystallized S])ecimen3) to 

 establish any meaiber of this family without the assistance of the 

 chemist or the microscope. I have no doubt that much of our feldspar 

 belongs to the tricliuic group, yet there is every reason to suppose the' 

 greatest bulk of the above bands is largely composed of the oblique 

 potash variety (orthoclase). In the township of Hull large clcavable 

 masses of a white, vitreous feldspar, enclosing a nucleus of a grey 

 material, make up considerable proportions of one of the above bands, 

 sometimes to the exclusions of the quartz altogether. Feldspar, in 

 some form, is almost invariably p»'esent, in more or less quantity, in all 

 the apatite veins, sometimes associated with hornblende, pyroxene, 

 quartz, sphene, <tc. 



Fine crystals of orthoclase are said to occur in Wakefield. In the 

 township of Hull on lot 7, range 1 2, beautiful flesh-red crystals occur 

 in cavities in a massive variety, and on the south half of lot 6, in the 

 same range, large cleavable masses of a green feldspar, associated with 

 a yellowish banded variety and a white translucent quartz, make up 

 large proportions of a band traversing this lot. Sometimes large, 

 brittle, black crystals of tourmaliue are intersj)ersed through this peg- 

 matite rock. 



Titanite or Sphene. — This mineral may also be regarded as a com- 

 mon associate of the ajiatite veins. Sometimes occurring massive in 

 lenticular patches in pyroxene rocks, at other tinies distributed in 

 crystals through various vein-stones. 



Rude ci'ystals of a brownish color occur in many places in the 

 township of Terapleton. In Hull, lot 12, range 13, imperfect crystals 

 of this mineral are so abundantly distributed through a pyroxene rock 

 jis to make up one-half its bulk. The finest crystals I have observed 



