CANADIAN APATITE. 35 



the side of a hill — an eminence apparently being favourable for the 

 outcrop of both veins and pockets. As an off-set against the uncer- 

 tainty in quantity, the quality is usually better than that of the 

 " stocks," the phosphate being less intermixed with gangue. Cavities 

 in veins often contain large crystals of apatite. 



The greater quantity is obtained, however, from lenticular masses 

 or '' pockets," which would appear to be segregations from the en- 

 closing rock matter, and more closely related to veins than to beds, 

 which latter they are supposed to be by some geologists. They are 

 from two to forty feet deep, and usually expand to a depth of a few 

 feet. Sometimes the phosphate is entirely surrounded by dead rock,, 

 and a shai'p line of demarcation may be drawn between them. When 

 such a pocket or stock is exhausted, the hole has often a basin shape, 

 in the bottom of which may sometimes be seen a thin streak of phos- 

 phate, perhaps only a few inches in width. In others, it would be 

 hard to say where the phosphate ended and the dead rock began, so 

 intermingled is the gangue. In a few instances borings, in 

 deserted pits, have revealed the pi-esence of phosphate at depths of 

 from ten to sixty feet. It is probable, therefore, that in many cases 

 further large deposits exist at lower levels. Almost all the apatite 

 hitherto mined has been obtained from surface deposits, and until 

 these are exhausted, little will be done toward developing these sub- 

 terranean beds, owing to the great expense in removing the superin- 

 cumbent rock matter. 



" Stocks " very often occur close together, say ten to twenty in an 

 area of five acres, with large intervening, perfectly barren tracts. 



The mineral, both of the veins and pockets, presents itself in 

 many varieties, both as regards colour and texture. The more com- 

 mon are the following : (1) Very fine granular, white, known as 

 " sugar." (2) Granular white, spotted with red, known as leopar- 

 dite. (3) Coarse and fine crystalline varieties of green, often tabu- 

 lar in cleavage. (4) Crystalline red varieties. (5) Violet, lustrous, 

 semi-translucent. (6) Pink, much harder variety, of feldspathic aspect. 



The operation of mining is extremely simple ; it should rather be 

 called a species of quarrying, except in a few cases where, quite 

 recently, shafts have been sunk and underground workings emploved 

 for the exti'action of apatite. Surface deposits being worked for the 



