158 
CONTRIBUTIONS    TO    ECONOMIC    GEOLOGY,  1905. 
Gold  and  platinum  contained  in  black-sand  concentrates  from  various  placer-mining  districts, 
by  States  and  counties — Continued. 
State  and  county. 
District. 
Ounces  per  ton 
of  concentrate. 
Number  of  sample. 
Gold. 
Plati- 
num. 
D  22 
CALIFORNIA— COn. 
Siskiyou 
do... 
Grouse  Creek 
10.31 
None. 
28.43 
9.02 
4.90 
1.99 
None. 
.05 
.34 
.37 
Trace. 
19.62 
1.60 
.52 
2.  02 
1.10 
Trace. 
Trace. 
1.06 
.16 
.  in 
6.  40 
1.67 
Trace. 
Trace. 
9.  90 
l.S 
None. 
.02 
Nolle. 
1.25 
4.71 
.50 
19.27 
.18 
Trace. 
1.88 
None. 
0.53 
0.18 
D  30 
Happy  Camp  district 
.82 
D20 
D  33 
Trinity. . 
Junction  Citv  mining  district 
25.  80 
do 
South  Fork  and  Trinity  River 
1.28 
4.61 
.43 
Trace. 
.05 
.06 
.09 
Trace. 
.18 
.70 
.11 
Trace. 
Trace. 
.05 
.04 
D  35 
do 
T.5N.,R.7E 
D  0037 
COLORADO. 
Chaffee 
Buena  Vista 
D  0033 
Costilla 
San  Luis  Valley 
junction  of  Gunnison,  Chaffee,  and  Pitkin 
counties. 
Pole  Creek,  Cretone 
D  6043 
Pitkin. . . 
D  6029 
Saguache 
D  0000 
San  Miguel 
do 
West   of  Tel  111  ride 
D  6016 
D  4012 
Idaho. 
Bingham 
West  of  Blackfoot 
D  4021 
D  4009.. 
Boise. . . 
( )xlio\v  tunnel.  I'avet  te  River 
D  4014 
do.... 
Cold  Fork    North  Payette  River 
D  4010 
Elmore 
Bear  Creek  mining  district.  Rocky  Bar 
Baker  Gulch,  Crooked  River 
D  4029 
D  4017... 
D  4034 
Elk  City  district 
D4023 
Shoshone...   . 
Pierce  City 
D4030 
do 
Pig  Island,  North  Fork  Clearwater  River. 
Beaver  Butte  mining  dist  rid  ,  Trail  Creek. 
.08 
D  4031 
do 
D  1004 
MONTANA. 
Granite 
.05 
Trace. 
Trace. 
.22 
D  9006 
NEW  MEXICO. 
Santa  Fe 
D9008 
Lincoln 
D2002 
OREGON. 
Baker 
South  of  Durkee 
I)  2009,  No.  1 
Old  Ocean   Beach,   Randolph  mining  dis- 
trict . 
do 
2.3 
91 
D2009,  No.  2 
do 
D  2009,  No.  3 
do 
do 
10 
D2045 
do 
Ocean  Beach,  Whiskey  River 
.20 
D2010 
do 
ti  23 
D2003 
East  of  Riddle 
s  5') 
D2006 
do 
Cow  Creek  mining  district,  Glendale 
Riddle 
North  Fork  Steamboat  River 
2.  25 
128  73 
D2023 
do 
D2028 
do 
do 
Josephine 
....  do 
.02 
D  2028,  No.  2 
D  2014a 
Bohemian  mining  district 
Trace. 
4  53 
D2021 
26 
D2029 
do 
Sucker  Creek 
.07 
