124 



a = {too}, Ь = {OIO}, m = {no}, e = {201}, 

 = {III}, и = {512}. 



What chiefly characterizes these small neptunite crystals 

 is their elongated prismatic form and the absence of the faces 

 of the third pinacoid. The same characters also belong to the 

 greater part of the neptunite material collected by me on Nar- 

 sarsuk. This form of development of the neptunite will be de- 

 scribed here as «type 11». 



The crystals of this type that I have found are not so 

 small as those observed by Nordenskiöld. They occasionally 

 attain a length of 2™ and a thickness of more than ^/2"". On 

 these crystals the following forms have been observed: 



a = {100}, m = {il0}, c?={30l}, e = [ш] , s = {lll}, 

 V = {221}, ^ = {311}, q = {Й2}. 



Not infrequently these crystals are attached in a manner that 

 has allowed of the development of crystallographic boundaries 

 at both their ends. The majority of individuals, however, are 

 attached by one end to their substratum. Specimens with 

 crystals thus attached are rather difficult to transport, because 

 the projecting pointed crystals are easily broken. 



The predominating faces are those belonging to the 

 vertical prism. They are well developed and bright. They often 

 show a fine tesselated striation consisting of a vertical striation 

 in combination with a striation parallel to the edge in which 

 they meet the form v. 



The faces of the first pinacoid are always coarsely striated 

 in vertical direction. Such a surface often looks as if it were 

 composed of a number of parallel columns which are not quite 

 on the same level. 



Among the terminal faces those of the pinacoid of the 

 second order, c?, are dominating. They are never quite bright, 

 but generally show only a faint shimmer. On them occur 

 numerous small depressions, the inside of which consists of 



