ransoms.] LODES OF GALENA MOUNTAIN AND VICINITY. 171 
the Silverton series. In its lower portions occur some rhyolite and 
intrusive masses of monzonite. The mass of the mountain is trav- 
ersed by very numerous lodes, in great part true veins, many of which 
are prominent on the surface. Only a few of the more conspicuous 
ones could be platted on the map, and those with merely approximate 
accuracy. The number, prominence, and rough parallelism of certain 
sets of these lodes suggest their division into at least four groups. 
(1) N. 45° E. lodes. — Lodes having a nearly northeast and south- 
west strike are not so numerous on Galena Mountain as they become 
farther north. The besl example in this portion of the quadrangle is 
the Ridgway lode, the general course of which is about N. 40° E., 
with local variations. Thus, in the Ridgway mine the strike, as 
observed in the drifts, is about N. (jo W. The lode dips southeast 
at from 75° to 80°. The Ridgway lode is faulted by the Alaska lode, 
with a strike of N. 40 W . 
(2) N.-S. lodes. — In this group are included a number of rather 
short lodes, of which the Yet a Madre may be taken as an example. 
They usually dip to the east al an angle of about 80°. No important 
ore bodies have been found on any of 1 hem, nor was any work on them 
in progress in L899. 'Hie Larger of these N.-S. lodes are of ten accom- 
panied by parallel Assuring and veining of the country rock. 
(3) N. 25° W. lodes. — Lodes of this group are very well seen on the 
south declivity of the mountain in the vicinity of the Veta Madre 
mine. The massive andesite is here traversed by a very prominent 
set of hssures running X. 25° W. and generally nearly vertical. The 
fissures are closely spaced, a foot or less apart, and are usually occu- 
pied by rather small stringers, which are sometimes mineralized. In 
the Yeta Madre tunnel the N.-S. lode is cut by a vein belonging to 
this group (N. 25° W.), which was followed for about 300 feet, and 
carried galena with chalcopyrite and probably sphalerite and pj'rite. 
The veins of this group are thus, in part at least, younger than the 
N.-S. veins of group 2. 
(4) N. 65° W. lodes. — Lodes whose courses are within a few degrees 
of N. 65° \Y£. are generally larger and more prominent than the other 
lodes of Galena Mountain. Just southwest of the summit of the peak 
a prominent lode of this group has been extensively prospected. The 
lode at this point is a large one, striking N. 60° W. and dipping 75° 
to the northeast. The ore is chiefly chalcopyrite and galena in a 
quartz gangue. The Neigold mine is also working one of these strong 
lodes (N. 75° W.), in this case practically vertical. The ore shows 
galena, chalcopyrite, a finely disseminated sulphobismuthite of lead, 
specularite, and pyrite, in a quartz gangue. A gray prismatic min- 
eral of brilliant metallic luster, determined as probably bismuthinile, 
is also present. The veins of this group cut the N. 25° W. veins of 
group 3, and in one case were observed to cut a vein striking about N. 
30° E. They are thus, as far as is known, the youngest veins on the 
mountain. 
