90 LABRADOR 



It would be tedious and not very profitable to the general 

 reader to describe all the different types of rock found in 

 the Basement Complex ; yet a few principal considerations 

 will serve to indicate the kind of material which goes 

 to form the bed-rock of the coast, and serve, also, to 

 outline the grand march of events that gave us modern 

 Labrador. 



With but rare exceptions the rocks of the Basement 

 Complex are allied to that most familiar rock, granite. 

 Like granite they are aggregates of common minerals like 

 quartz, feldspar, mica, hornblende, augite, magnetite, etc. 

 These are always crystalline, though rarely does any mineral 

 show crystal facets to the eye. The minerals interlock 

 in the intimate way characteristic of granite. Further- 

 more, these rocks bear witness to one common fact of origin 

 with granite. They formed, crystallized, under the press- 

 ure of overlying rock which has long since been swept away 

 eaten away by the weathering and decay of ages, eroded 

 by the " tooth of Time." Many of the individual rock- 

 masses are known to have resulted from the crystallization 

 of once molten rock-material, cooled slowly as its heat was 

 conducted through the heavy cover of rock above. Such is 

 believed to have been the origin of all granites. Others of 

 the Labrador rocks seem to have crystallized at a tempera- 

 ture high enough to allow of the rearrangement of their 

 ultimate particles from former quite different associations, 

 yet at a temperature too low for actual fusion of the rocks. 

 Such are the conditions within the heart of a mountain- 

 range as it grows, its rocks crumpling together, piling .up, 

 fracturing, and making way before great bodies of the 

 molten matter erupted from the interior of the earth ; such 



