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QUARTZ, AS IT OCCURS IN THE LAKE DISTRICT; 

 ITS STRUCTURE AND ITS HISTORY. 



By J. Clifton Ward, F.G.S., F.R.M.S. 



Introduction. 



I. Geological Distribution. 



Vein Quartz, tinder four conditions. 



Quartz as a Rock Constituent, 



(a) Of Stratified Rocks. 



(b) Of Unstratified and Volcanic Rocks. 



1. Among Granitic and Granitoid Rocks. 



2. Among Intrusive Diorites, Dolerites, &c. 



3. As an Accidental Constituent. 



II. Quartz as a Microscopic Study. 



Introduction. 



There are few minerals more widely spread than Quartz, a 

 chemical compound of the two elements Silicon and Oxygen. 

 Common though this mineral is, however, its study opens out 

 questions of deep interest, and may lead us from the contemplation 

 of a pretty piece of rock-crystal to the consideration of subtle and 

 hidden processes in the formation of the crust of our globe. 



/ GEOLOGICAL DISTRIBUTION. 



Quartz occurs among our Lake-country mountains in several 

 forms, but never as a rock by itself, in thick bedded masses, as is 

 occasionally the case in other mountain tracts. 



