146 



quantity of elpidite needles loosely agglomerated were found at 

 some depth below the surface. They had been protected from 

 the atmosphere and were snow-white and tolerably fresh. The 

 mass was so loose that it could often be broken into pieces 

 with the hands. On pressure it yielded and fell asunder into 

 gravel with a crackling sound. The whole was traversed by 

 larger aegirine crystals, which thus formed a sort of skeleton 

 in the fragile aggregate. In the numerous spaces between the 

 elpidite needles several other minerals occurred in crystals. 

 There were small well-developed crystals of epididymite, albite, 

 polylithionite , leucosphenite , etc. The last mineral was found 

 only in small quantity. Like the other minerals mentioned here, 

 it is of later formation than the elpidite. Elpidite needles some- 

 times traverse the leucosphenite crystals, which, however, have 

 been formed earlier than the albite. The crystal No. 8, which 

 is of a type differing from the others, was found on a specimen 

 from the locality No. I. 



29. Elpidite. 



By the name elpidite G. Lindström ^) designated a pre- 

 viously unknown mineral which he had observed in the Liitzen 

 collection. In his article he chiefly gives an account of the 

 way in which he analyzed the mineral and the result of his 

 analysis. To the latter we shall return later on. Lind s trom 

 further gives a statement of the physical properties of the 

 mineral as observed by him. He describes it as finely columnar, 

 forming long sheaves. Occasionally the columns are short and 

 confusedly intergrown. Sometimes they are matted together 

 into a half- compact, felt- like, brick -red mass. The mineral 

 occurs on aegirine crystals and sometimes fills up the drusy 

 cavities in which the latter occur. It is, further, accompanied 



Ï) Geol. Foren. Forhandl. Vol. 16, 1894, p. 330. 



