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G. Nord enskiöid, and 1 have been able to satisfy myself 

 that the same mineral occurs among those collected by me on 

 JNarsarsuk. The material collected by me occurs on several 

 specimens , but in so small quantities that the procuring of 

 material for a more accurate analysis was impossible. The fol- 

 lowing observations therefore concern only the exterior charac- 

 ters and the mode of occurrence of the mineral. 



The octahedral crystals are extremely diminutive , never 

 attaining even 1™"" in diameter. Most of them cannot even be 

 distinctly observed under a strong magnifying-glass. The octa- 

 hedral form is generally fairly regular; often, however, the 

 crystals are deformed, sometimes by showing a tetrahedral 

 development, sometimes by being elongated prismatically in 

 the direction of an octahedral edge. Besides the principal form 

 (the octahedron), minute faces belonging to the hexahedron 

 {lOO) have been observed under the microscope. On some of 

 the specimens the crystals are sharply developed with smooth 

 and brilliant faces; on other specimens they are highly rounded 

 and indistinct. 



In colour these crystals vary somewhat. The largest and 

 most distinct individuals are brownish yellow inclining to red. 

 The less distinctly developed and rounded crystals are greenish 

 yellow with a tinge of brown. On one specimen occur ex- 

 tremely small crystals forming crusts; these are quite white or 

 colourless. 



These crystals, determined by G. Norden skiold as 

 microlite , have been found only at the locality No. 3 on Nar- 

 sarsuk. The specimens on which the mineral occurs lay loose 

 among the gravel. Single crystals and crusts of crystals occur 

 implanted mostly on larger aegirine individuals associated with 

 secondary needles of aegirine and several other minerals as 

 polylithionite, albite, elpidite, etc. Traces of catapleiite of type III 

 have also been observed together with microlite. 



