312 THE CANADIAN NATURALIST. [Vol. viii. 



APATITE : ITS MODE OF OCCURRENCE IN 

 NORWAY. 



The February number of The British Mercantile Gazette 

 contains an interesting article on " Norwegian Phosphates," which 

 we republish here, somewhat abridged, in the belief that it 

 cannot fail to prove of value to such Canadian readers as may 

 be interested in the great apatite deposits of Burgess and Ottawa 

 County. 



The palaeozoic rocks of Norway correspond so closely to our 

 Laurentian series, and the modes of occurrence of the chief de- 

 posits of minerals of economic value are so similar in the two 

 re°ions that any practical information about the Norwegian apa- 

 tite must benefit those engaged in mining here. 



" It is, relatively speaking, but a few years since the Nor- 

 wegians learnt the value and importance of their apatite mines. 

 These mines are generally found at the bottom of granite rocks, 

 and where the mines exist there appears on the surface an out- 

 crop of the bed. These veins proceed from the principal deposit; 

 they are of variable dimensions, but ordinarily very large, from 

 100 to 200 feet deep. . . . They are narrow at the surface, 

 generally increasing in size as they approach the nucleus. A few 

 of these veins contain, at variable distances, irregular pockets, 

 more or less spherical, from six to eight feet iu diameter, called 

 roses. 



" Those who were first engaged in the extraction of apatite, 

 contented themselves with emptying these pockets. . . The 

 veins are always enclosed in the granitic strata, and are conform- 

 able to their dip. At times the vein is suddenly broken and 

 interrupted by the presence of an irregular mass of rock, but by 

 continuing the work of extraction it will be found again in the 

 same direction, a few inches lower, and ordinarily larger. It 

 was through inexperience on the subject that in the beginning 

 the Norwegians only worked the veins a short depth and then 

 abandoned them. 



11 The greater part of the veins of apatite are surrounded by a 

 thick layer of black mica or of hornblende. Science has not yet 

 been able to determine the cause of their presence in this case 

 where they enclose the apatite like a sheath or thin skin existing 

 between the granite and the apatite vein. . . . The name 



