﻿GEOLOGY 
  OF 
  THE 
  NORTH 
  CREEK 
  QUADRANGLE 
  85 
  

  

  Pottersville 
  ; 
  while 
  the 
  third 
  is 
  by 
  the 
  State 
  road 
  334 
  miles 
  north- 
  

   northeast 
  of 
  North 
  Creek. 
  

  

  The 
  Grenville 
  gneisses 
  are 
  nearly 
  always 
  of 
  poor 
  quality 
  for 
  

   road 
  work 
  because 
  of 
  the 
  high 
  quartz 
  and 
  mica 
  content 
  and 
  the 
  

   heterogeneity 
  of 
  the 
  rocks 
  which 
  are 
  in 
  layers 
  of 
  varying 
  com- 
  

   position. 
  In 
  spite 
  of 
  this, 
  one 
  quarry 
  for 
  State 
  road 
  purposes 
  has 
  

   recently 
  been 
  operated 
  near 
  the 
  southeastern 
  end 
  of 
  Loon 
  lake. 
  

  

  BUILDING 
  STONE 
  

  

  There 
  is 
  an 
  inexhaustible 
  supply 
  of 
  building 
  stone 
  of 
  excellent 
  

   quality 
  within 
  the 
  map 
  limits. 
  The 
  syenite, 
  granite, 
  and 
  granite 
  

   porphyry 
  all 
  rank 
  as 
  very 
  strong 
  and 
  durable 
  building 
  stones. 
  Of 
  

   these 
  the 
  granite 
  porphyry 
  would 
  perhaps 
  make 
  the 
  most 
  effective 
  

   and 
  beautiful 
  stone 
  when 
  highly 
  polished 
  because 
  of 
  the 
  large, 
  

   scattering, 
  pink, 
  feldspar 
  crystals 
  which 
  are 
  set 
  in 
  the 
  much 
  finer 
  

   grained 
  gray 
  matrix. 
  The 
  color 
  of 
  this 
  rock 
  would 
  remain 
  practi- 
  

   cally 
  unaltered 
  on 
  exposure 
  to 
  the 
  weather. 
  Some 
  of 
  this 
  rock 
  from 
  

   the 
  quarry 
  at 
  Horicon 
  is 
  said 
  to 
  have 
  been 
  used 
  in 
  the 
  State 
  Capitol 
  

   at 
  Albany. 
  The 
  pink 
  granites, 
  too, 
  would 
  make 
  beautiful 
  and 
  very 
  

   durable 
  building 
  stones 
  not 
  subject 
  to 
  color 
  change. 
  The 
  syenites, 
  

   which 
  are 
  generally 
  greenish 
  gray 
  when 
  fresh, 
  would 
  weather 
  to 
  

   light 
  brown 
  on 
  exposure 
  to 
  the 
  atmosphere 
  but, 
  as 
  regards 
  dura- 
  

   bility 
  and 
  strength, 
  they 
  would 
  be 
  excellent 
  stones. 
  These 
  igneous 
  

   rocks 
  are 
  considerably 
  used 
  locally 
  but 
  because 
  of 
  the 
  distance 
  

   from 
  population 
  centers, 
  no 
  quarries 
  have 
  been 
  opened 
  up 
  for 
  ship- 
  

   ping 
  purposes. 
  The 
  pinkish 
  gray 
  granite 
  used 
  in 
  the 
  construction 
  

   of 
  the 
  new 
  Warrensburg 
  High 
  School 
  building 
  was 
  obtained 
  from 
  

   the 
  south 
  side 
  of 
  Hackensack 
  mountain 
  and 
  just 
  off 
  the 
  map. 
  

  

  The 
  only 
  stone 
  which 
  has 
  been 
  quarried 
  for 
  shipping 
  purposes 
  

   is 
  the 
  green 
  marble 
  or 
  so-called 
  verde 
  antique 
  of 
  the 
  Grenville 
  

   series. 
  Though 
  occurring 
  at 
  a 
  number 
  of 
  localities, 
  the 
  only 
  place 
  

   where 
  quarrying 
  has 
  been 
  done, 
  and 
  this 
  years 
  ago, 
  is 
  one-half 
  of 
  

   a 
  mile 
  west-southwest 
  of 
  Thurman 
  village. 
  This 
  rock 
  is 
  a 
  medium 
  

   grained, 
  white 
  to 
  greenish 
  gray 
  marble 
  through 
  which 
  are 
  scattered 
  

   many 
  streaks 
  and 
  blotches 
  of 
  bright 
  green 
  serpentinous 
  material, 
  

   so 
  that 
  the 
  polished 
  stone 
  presents 
  a 
  striking 
  effect. 
  

  

  