382 
CONTRIBUTIONS    TO    ECONOMIC    GEOLOGY,  1905. 
one  known  instance,  near  Springdale,  where  the  semicrystalline  limestone  contains  cod  ( 
remains  which  indicate  its  Paleozoic,  probably  Carboniferous,  age.     While  these  rocks  ai  I 
ordinarily  known  as  limestones,  many  of  them  are  really  dolomites,  and  careful  field  wor 
must  be  done  and  many  analyses  .made  in  order  to  locate  the  true  limestones  and  determiu 
their  extent . 
The  only  place  in  Stevens  County  where  active  steps  have  been  taken  toward  the  mar. 
ufacture  of  cement  is  ai  Box  Canyon,  on  Pend  Oreille  River.  It  is  planned  to  trans 
port  the  cement  by  steamer  up  the  river  45  miles  to  Newport,  where  the  Great  Norther. 
Railway  is  reached.  At  Box  Canyon  there  are  large  deposits  of  pure  limestone  and  bed 
of  excellent  clay,  as  well  as  layers  of  natural  cement  rock  interst  rat  ified  with  the  pur 
limestone.  The  Pacific  Port  land  Cement  Company  has  acquired  2(>2  acres  of  land  and  ha 
expended  $20,000  in  preliminary  work.  A  dam  has  been  made  across  Cedar  Creek  abou 
3  miles  above  its  confluence  with  the  Pend  Oreille  at  Box  Canyon,  and  by  the  use  of  a  flurrn 
and  a  28-inch  steel  pen-lock  with  Pelton  wheel  about  250  horsepower  is  obtained.  Tin 
works  now  under  construction  will  have  a  daily  capacity  of  200  barrels.  Analyses  of  tHi 
imestone  and  clay  ai  Box  Canyon  are  as  follows: 
Analyses  oflimestom  and  clay  from  Box  Canyon,  Washington. 
Silica 
Aluminum  and  iron  oxides 
Calcium  carbonate 
ite . . . 
In  the  vicinity  of  Colville,  on  the  Spokane  Falls  and  Northern  Railway,  there  are  some 
occurrences  of  limestone  free  From  magnesium  carbonate  in  harmful  amounts.  One  of  these 
occurrences  is  ai  a  point  15  miles  northeast  of  Colville,  where  the  Jefferson  Marble,  Mini™ 
and  Milling  Company  has  opened  a  quarry  and  established  marble  works.  The  limestone 
outcrops  cover  a  broad  area  with  extensive  l>eds  of  glacial  clays  conveniently  near.  The 
limestone  or  marble  exhibits  many  varieties  of  colors,  from  clear  white  through  yellow, 
brown,  and  dark  blue  to  Mack.  The  stone  is  fine  grained  and  compact.  Analyses  of  twe 
varieties  of  marble,  made  by  Prof.  S.  Shedd,  of  Pullman,  are  as  follow-; 
Analyses  ofwhitt  and  pink  marblefrom  quarry  15  miles  northeast  of  Colville,  Wash. 
U  liito 
marble. 
I'ink 
marble. 
Silica 
0.87 
None. 
None. 
55.16 
.21 
43. 77 
A.& 
J  roil 
.2 
Alumina 
None 
Lime 
.r)1.5' 
Magnesia, 
1.11 
Carbon  dioxide 
42.  4( 
