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J. V. EMen — Origin of Pegmatite Veins. 



type described by Brogger in the Christiania district. Unfortunately, 

 the time at my disposal did not allow an exhaustive examination of 

 this large district, and my present remarks are written rather with 

 the hope of eliciting further information than with any claim to the 

 establishment of a final conclusion. 



Fig. 1. — Contorted pegmatite vein in granite, Gungvala, near Carlshamu, Sweden. 

 Scale, 1 incli = 2 feet. 



At Gungvala, on the railway running inland from Carlshamn, 

 I saw thin pegmatite veins, often not more than a few inches wide, 

 sharply folded as in the accompanying diagram (Fig. 1). The- 

 amplitude of the folds is seldom more than a couple of feet, but 



Fig. 2. — Folded pegmatite in a sett quarry, Gungvala, Sweden. The parallel lines- 

 are joint planes. Scale, 1 inch = 10 feet. 



there is no sign that these folds influence the parent rock. A striking 

 example is shown in Fig. 2, where the folds taper downwards, 

 diminishing in amplitude, while the veins themselves contract in 

 M^idth. The junction between the granite and pegmatite is clean 

 and complete, without any druses or other interruptions that could 



