﻿Plate 
  4 
  

  

  W. 
  J. 
  Miller, 
  photo 
  

   A 
  typical 
  exposure 
  of 
  gabbro 
  as 
  seen 
  three-fourths 
  of 
  a 
  mile 
  south-south- 
  

   west 
  of 
  Loon 
  Lake 
  mountain. 
  Note 
  the 
  very 
  irregularly 
  jointed 
  character 
  

   of 
  the 
  rock 
  and 
  the 
  whitish 
  mass 
  of 
  pegmatite 
  cutting 
  the 
  gabbro 
  in 
  the 
  

   lower 
  left-hand 
  corner. 
  

  

  