170  CONTRIBUTIONS    TO    ECONOMIC    GEOLOGY,   1903.  [bull.  225. 
Mineral  productions  of  Redding  quadrangle  for  1902— Continued. 
Lime - barrels. . 
Limestone tons.. 
Clay M  brick.  - 
Chromite tons. . 
Pyrite do 
Total 
Quantity. 
18,  500 
3,  500 
2,  450 
315 
3,202 
Value. 
$12,  500.  00 
3,  600.  00 
12,  250.  00 
4,  725.  00 
7,  005. 00 
3,135,060.15 
GOLD. 
GOLD   OF   PLACER    MINES. 
In  the  early  fifties,  millions  of  dollars'  worth  of  gold  were  gathered 
from  the  placer  mines  about  the  northern  end  of  the  Sacramento  Val- 
ley, especially  in  the  vicinity  of  Horsetown,  Shasta,  and  Buckeye,  but 
as  these  shallow  gravels  became  exhausted  or  hydraulic  mining  was 
restricted  by  laws  concerning  debris  more  attention  was  given  to 
quartz  mining,  and  lately  to  the  development  of  copper  ores  containing 
gold  and  silver. 
During  the  winter  and  spring,  when  water  is  plentiful,  there  is  still 
much  placer  mining  in  a  small  way  in  the  Redding  quadrangle,  but 
trustworthy  returns  are  available  from  scarcely  a  dozen  mines,  showing 
a  yield  in  1902  of  but  little  over  $500.  The  greatest  activity  was  on 
Dog  Creek,  west  of  Delta,  where  work  was  continued  at  several  points 
during  the  summer  upon  the  lower  benches  and  stream  bed.  In  the 
valley  of  Squaw  Creek,  near  Copper  City  and  Delamar,  half  a  dozen 
placers  were  reported  in  1902.  Their  values  appear  to  have  been 
derived  largely  from  the  leached  copper  ores,  which  leave  most  of  the 
iron-stained  gossan  near  the  surface  to  find  its  way  into  the  placers. 
The  gold  in  the  placers  of  Dog  Creek,  as  well  as  about  Shasta,  Old 
Diggings,  and  Buckeye,  is  all  derived  from  the  quartz  veins  which  occur 
in  the  igneous  rocks  of  the  region.  In  the  early  days  the  stream 
beds  were  rich  with  the  accumulations  of  ages.  Having  been  worked 
over  they  are  now  impoverished,  but  as  erosion  progresses,  in  the 
course  of  time  they  will  doubtless  be  again  enriched.  The  rate  of 
enrichment,  however,  is  so  slow  as  to  amount  to  comparatively  little 
within  a  generation. 
During  the  summers  of  1902  and  1903  a  suction  dredger  was  operated 
irregularly  at  various  places  in  Sacramento  River,  near  the  mouth  of 
Middle  Creek,  3  miles  above  Redding,  and  it  is  said  that  the  work  is 
to  continue.  A  larger  dredger,  with  a  series  of  buckets  on  an  endless 
chain,  was  installed  on  the  flat  by  the  side  of  Clear  Creek,  below  Horse- 
