126 



made show the bodies of mineral to be of 

 extremely irregular shape, merging into the 

 enclosing rock, and holding varying propor- 

 tions of inter-mixed rock. At places very 

 large bodies of almost pure phosphate have 

 been encountered, yielding many thousands 

 of tons." 



The phosphate of this district is usually 

 closely associated with mica and pink calcite, 

 and in the early days of the mining industry, 

 the mica was removed and went to the dump 

 as a waste product — many hundreds of tons 

 in this way being lost to commerce. In actual 

 mining it was frequently found that the phos- 

 phate was of little economic value when it 

 occurred with calcite and mica, for the amount 

 was insufficient to repay the actual cost of its 

 separation by itself. The great economic 

 deposits of the mineral were those in which 

 the apatite was found in large pockets without 

 much mica being present. It would therefore 

 appear that certain deposits within the 

 pyroxenite are composed essentially of apa- 

 tite, mica, and pyroxene; while others are 

 essentially calcite, mica, and pyroxene. Nat- 

 urally there will be deposits of intermediate 

 character where calcite, apatite, mica, and 

 pyroxene will be intimately associated. It is 

 also clear that many of the phosphate mines 

 later became mica mines, especially as the 

 phosphate industry in Canada was soon 

 displaced by that of the Southern States. 



The phosphate in this district carried 80 

 per cent or more of calcium phosphate. 

 This was shipped to the town of Smith's Falls, 

 on the Rideau Canal, and was there manu- 

 factured into fertilizers. The mineral was 

 ground by buhr-stones to 100 mesh, then 

 conveyed to a vat with sulphuric acid, where 

 it was agitated for twenty-four hours. Hydro- 

 fluoric acid was liberated, and allowed to pass 

 off into the air, while in the vat a precipitate 

 of calcium sulphate was formed, and calcium 

 acid phosphate went into solution thus: — 



