36 
DEPOSITS OF PHOSPHATE OF LIME. 
[BULL. 
mixed and associated with small quantities of scapolite, zircon, sphene, 
talc, hornblende, specular iron ore, zeolites, and other minerals. Veins 
also occur which are almost entirely composed of apatite crystals scat- 
tered in a matrix of granular quartzite. 
On the land of the Anglo-Canadian Phosphate Company, at Otty Lake, 
North Burgess, where some of these veins have been opened to a depth of 
seventy to eighty feet, the mode of occurrence of the apatite is well seen. 
The prevailing country rock here is quartzite and garnetiferous gneiss. 
In some cases the line of division between the vein matter and the coun- 
try rock is sharply drawn, while in others they gradually blend. Both 
of these phenomena, as well as the banded and the unbanded structure, 
are often seen in different parts of the same vein. The apatite occurs in 
bunches, sometimes connected by seams of the same mineral. From a 
single one of these bunches over a thousand tons have been taken. 
lis :•;:;:-: 
Fig. 19. Section at McKenzie's opening, looking EKE., Bowman, Ottawa County, Quebec, Canada. 
A, apatite, witb. pyroxene crystals; B, pyroxene; C, limestone. Scale: 1 inch = 50 feet. 
The contents of the phosphate- bearing veins are often very variable 
at different points in the same vein, sometimes consisting mostly of apa- 
tite, scapolite, feldspar, and pyroxene, aud at others beiug composed of 
crystalline limestone bearing crystals of the above minerals. Such a 
formation is seen on Henry Barr's land, in Eenfrew County. At the 
McKenzie mine, in Bowman Township, Ottawa County, Quebec, there 
is a vein in a hill of lilac-colored feldspar and pyroxenite. One part of 
the vein is composed of massive apatite, holding crystals of pyroxene 
and scapolite, while another about fifty feet distant assumes a totally 
different character, being composed of a pink, crystalline calcite, bearing 
crystals of apatite. In some places the calcite has been worn away by 
the infiltration of water, and then the structure of the vein can be seen. 
The cavity is lined with crystals of scapolite and pyroxene, which come 
next to the country rock, while the calcite, bearing the crystals of apa- 
tite, comes in the middle (Fig. 19). This formation of drusy cavities in 
limestone leads is very common, especially in the Ontario district. Often 
the calcareous matter has been washed away, aud crystals of apatite 
and their fragments are scattered over the bottom of the hollow. The 
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