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 34. Apatite. 



The only mineral containing phosphorus that has been 

 found on Narsarsuk is apatite, and it occurs there but sparingly. 

 The mineral has been met with only in the crystallized stale. 

 The crystals are generally of very small dimensions and present 

 three distinct types of development, each of which has been 

 found at a separate locality, and associated with different 

 minerals in each case. I give here a description of the 

 different types. 



Type I. (Yt trin m -apati te). 



The apatite crystals of the first type seldom attain more 

 than 1 """ in their greatest diameter. They are bounded exclu- 

 sively by the hexagonal prism and the base without a trace of 

 other forms. They are either short prismatic in the direction 

 of the vertical axis or thickly tabular parallel to the base. In 

 most cases the section parallel to the principal axis is of about 

 the same size as the section parallel to the lateral axes, i. e. 

 the length and thickness of the prismatic crystals are nearly 

 equal. As regards their development they are rather perfect. 

 The planes are smooth and brilliant, the edges and corners 

 sharp. On the prismatic faces often occurs a feeble striation 

 in vertical direction. 



In general the crystals are attached by faces belonging to 

 the prismatic zone, the principal axis being parallel to tlie 

 substratum. When, as is most frequently the case, many 

 individuals are grown together into druses, they often occupy 

 a parallel positio-n with reference to one another, forming step- 

 like groups and aggregations. 



The colour of the mineral is enamel-white, its lustre is of 

 rather an uncommon character, the crystals showing a marked 

 metallic lustre like that occurring on the surface of newly molten 

 silver. This lustre is most characteristic of these crystals. Tlie 



