202 GEOLOGY AND GOLD DEPOSITS OF THE CRIPPLE CREEK DISTRICT. 
Partial analyses of oxidized and fresh ore from the Moose mine. 
[Analyst, F. C. Knight.] 
Unoxi¬ 
dized 
portion. 
Oxidized 
portion. 
Unoxi¬ 
dized 
portion. 
Oxidized 
portion. 
Silica. 
56.70 
50.55 
Sulphur. 
Alumina. 
19.35 
19.93 
Sulphur trioxide. 
2.55 
Iron. 
4. 20 
Tellurium. 
. 10 
Ferric oxide. 
10.57 
Tellurium oxide (TeO). 
.79 
Magnesia. 
.37 
.12 
Silver. 
.022 
None. 
Alkalies (by difference). 
.13.967 
12.131 
Gold. 
.041 
.049 
. 27 
Water. 
.50 
3.05 
100 
100 
In the fresh portion only 1.35 per cent of the alumina was soluble in hydro¬ 
chloric acid, while in the oxidized portion 3.18 per cent proved soluble. In the 
latter a hydrated basic ferric sulphate was proved to be present. 
In order to obtain further light upon the results of oxidation, some very rich, 
wholly oxidized ore from a vein in the breccia on the 100-foot level of Stratton’s 
Independence mine was obtained through the kindness of Messrs. C. M. Becker 
and W. N. Travell, of the mine staff. The soft, dark-brown, powdery ore in two 
samples from different places was subjected to analysis by W. F. Hillebrand with 
the following result: 
Analyses of oxidized ores from Cripple Creek. 
1. 
2. 
1 . 
2. 
54.45 
BBO. 
0.0025 
0.0025 
Ti0 2 . 
.80 
M0O3. 
.018 
.008 
14. 45 
.36 
. 19 
a 9.94 
Au. 
.35 
.52 
MnC >2 . 
1. 71 
Ag. 
None or trace. 
.02 
CaO. 
1.14 
so 3 . 
. 10 
MgO. 
.48 
p 2 o, . 
. 
.50 
K 2 0. 
9.96 
h 2 o. 
Na20. 
. 41 * 
co 2 . 
Trace. 
ZnO 
c 53 
CuO.'. 
0.03 
.03 
95. 4205 
PbO. 
. 
.18 
a Both Fe20 3 and FeO present. & Both MAO 2 and MnO present. c Possibly high. 
There are no sulphides. The difference is largely made up of combined water. 
From the analyses and from what is known about the normal composition of 
unoxidized ore the following conclusions may be drawn, although it is of course 
realized that much more analytical work would be necessary for an exhaustive 
treatment of this difficult subject. 
During oxidation the percentage of silica decreases moderately, probably by 
solution of silica set free during the decomposition of silicates. Alumina remains 
fairly constant, though it may locally concentrate to pure kaolin. The iron is apt 
to locally increase by concentration as limonite, though a part will be carried away 
as sulphate. Small amounts of lime and magnesia are probably leached from the 
