318  CONTRIBUTIONS    TO    ECONOMIC    GEOLOGY,  1904.        [bull.  26| 
Production  of  iron  ore  in  the  United  States  in  1903,  etc. — Continued. 
State 
Red  hematite. 
Brown 
hematite. 
Magnetite. 
Carbon- 
ate. 
Total. 
Texas 
34, 050 
8,900 
30, 729 
34, 05» 
32, 227 
Kentucky  _           
23, 327 
Connecticut    and    Massa- 
chusetts 
30, 729 
Ohio 
• 
29, 688 
5,145 
29, 6881 
Maryland 
4, 775 
9,920 
Total . 
30, 328, 654 
3, 080, 399 
1,575,422 
34,833  !  35,019.308 
1 
These  figures  can  be  put  into  more  serviceable  form  by  classing  j 
the  ores  according  to  their  geologic  and  geographic  distribution.  I 
As  shown  below,  5  quite  distinct  classes  can  thus  be  formed.     Taken 
together  these  five  classes  will  account  for  over  99  per  cent  of  the 
total  iron-ore  production  of  the  United  States,  leaving  unclassified 
less  than  1  per  cent. 
Of  these  5  classes  the  first  consists  of  the  ore  from  the  well-known! 
Lake  Superior  district.  The  three  classes  next  in  importance  agree 
geographically  in  being  all  located  in  the  eastern  and  southeastern 
United  States,  but  differ  in  the  character  and  geological  association 
of  their  ores.  The  fifth  class  includes  an  ore  district  in  the  Rocky 
Mountain  States  of  great  promise  but  as  yet  slightly  developed. 
The  relative  importance  of  these  five  classes  as  producers  is  showm 
in  the  table  below : 
Production  of  iron  ores  in  the  United  States  in  1903,  by  classes. 
. 
Long  tons. 
Per  cent 
of  total,  i 
Lake  Superior  ores 
Clinton  fossil  ores 
Appalachian  Valley  limonites 
Eastern  magnetites 
Rocky  Mountain  ores 
Unclassified 
Total 
26,617,768 
3, 372, 557 
2,731,329 
1,425,182 
645, 151 
227, 321 
76 
9.6 
7.8 
4.1 
1.8 
.7 
35,019,308 
100 
The  characteristics  of  these  classes  of  iron  oros  and  the  work  that 
has  been  done  by  this  Survey  in  the  various  districts  may  be  briefly 
summarized  as  follows : 
