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Tutop Agdlerkofia is older than the steenstrupite of type I oc- 

 curring there. As regards the last mentioned occurrence it is 

 still to be remarked, that in all localities where the sodahte, 

 which is there of a strong yellow color, appears in greater 

 quantities, the steenstrupite is formed according to type II. 

 This formation is only found in one single case in the albite 

 itself at Tutop Agdlerkofia, while on the other hand it occurs 

 in the two other localities almost exclusively in the grained 

 albite. 



Where the steenstrupite occurs South of the Firth of 

 Tunugdliarflk it is found chiefly in the pegmatite-veins, however 

 it is also often found together with considerable quantities of 

 grained albite. It comes in contact here with a very great 

 number of minerals, among which the principal ones are 

 albite, microcline-microperthite, aegyrite, arfvedsonite, nephelite, 

 sodalite, polylithionite , eudialyte and sphalerite besides many 

 more very rare and partly new minerals. Though the age 

 relations are rather difficult to state , it is however found 

 that the steenstrupite has crystallized before almost all the 

 minerals mentioned. The only one of them, which in most 

 cases is older, is the aegyrite, which is therefore often seen to 

 pass right through the middle of the steenstrupite crystals and 

 as above mentioned to be found quite embedded in it. Where 

 the steenstrupite occurs principally surrounded by aegyrite on 

 all sides, it then perfectly looses its crystalline form and occurs 

 as massive steenstrupite. 



Chemical properties. Since the crystals of type III according 

 to the physical properties must be supposed to represent the 

 least altered form of steenstrupite the chemical composition is 

 stated here from an analysis made by cand. polyt. Chr. Chri- 

 stensen. For comparison are given two of the analyses, 

 made by Blom strand, mentioned by Mo berg, of the 

 steenstrupite from Kangerdluarsuk. 



