212 ECONOMIC GEOLOGY OF SILVERTON QUADRANGLE, [bull. 182. 
A crosscut tunnel of about 250 feet, running <\ little west of north, 
gives access to the vein on the No. 1 level. Below this level, at inter- 
vals of 125 feet, are levels 2 and 3, worked through a shaft from No. 
1 level. The lode as a rule is an unusually regular plate of ore, hav- 
ing an average width of about 18 inches and generally frozen to the 
walls. Less frequently it is a regular sheeted zone, 3 or 4 feet wide, 
the stringers of ore and quartz showing comb and vug structure. 
Even where the lode, is a simple solid vein a foot in width, the walls, 
especially the foot wall, may show conspicuous sheeting for some dis- 
tance from the ore. The hanging wall is usually smooth and regu- 
lar. The country rock of the portions of the vein now worked is 
andesitic breccia of the San Juan series. 
The ore consists of galena and sphalerite, with a little free gold, 
argentite, and wire silver, in a gangue of quartz, rhodochrosite, and a 
little fluorite. A banded structure is often very noticeable. A typ- 
ical section of the vein as seen in one of the stopes is shown in fig. 5 
(p. GO). In this case the stringers of barren-looking quartz next the 
walls appeared to be of later age than the banded ore between them. 
The average value of the Japan ore is about $25 per ton. Nearly 
one-half of this is in gold, the other being equally divided between 
silver and lead. All the ore, excef)t a little streak of rich lead ore, 
which often occurs in veins, is milled. 
About 150 feet northeast of the Japan vein is a second parallel 
lode — the Morning vein — with the same general dip as the Japan. 
Where cut by the Mikado crosscut from the No. 1 level of the Japan, 
this vein is only 5 inches wide and carries galena ore, frozen to the 
walls. Elsewhere it is wider and often carries much coarsely crystal- 
line pale-green and white fluorite. This lode is not worked. 
About 750 feet northeast of the Morning vein the Mikado crosscut 
passes through a third parallel vein, here not much more than a fissure 
carrying some gouge. In all, the Mikado crosscut has been driven 
nearly 1,900 feet to the northeast in the hope of cutting the continua- 
tion of the Tomboy lode. Several small fissures, generally parallel, 
with the Japan lode, have been cut, but none of them cany ore in 
commercial quantities. Apparently the Tomboy lode does not con- 
tinue so far to the northwest, or else is diminished in size and changed 
in character so as to be unrecognizable. 
The Japan and Morning veins are both faulted by the Flora vein, 
with a course of N. Q5° E. and a dip of 55° or 60° to the southeast. 
This is a barren quartz vein about 2 feet wide filling a fault fissure 
which has thrown the southeastern portion of the Japan and Morning 
lodes about 1G feet to the southwest. This same vein probabh 7 faults 
the Tomboy lode also, in ground not yet explored, and may be con- 
nected with the failure of the Tombo}- to appear in the Mikado cross- 
cut. The position of the Flora vein is well marked on the surface, as 
its outcrop determines the presence of a little ravine. 
