408 GEOLOGY AND GOLD DEPOSITS OF THE CRIPPLE CREEK DISTRICT. 
To summarize, there are two principal ore shoots on the basalt dike. One 
begins at the surface 130 feet, pitches steeply to the south, and gradually shortens 
till it pinches out about 385 feet below the surface. This shoot is fairly regular in 
form and the values are pretty evenly distributed through it. The second shoot, 
which is directly below the first, begins at the 470-foot level and has been proved to 
the 850-foot level. It is irregular in form and the values which it carries vary 
greatly in different parts. 
DELMONICO MINE. 
The Delmonico claim, on which the mine is located of the same name, lies on 
the western slope of Bull Cliff, just east of Deadwood. It belongs to the Stratton 
estate and is worked by lessees. The development consists of a shaft 600 feet deep, 
300 feet of which have recently been completed, and three levels at 100-foot inter¬ 
vals. Development in the lower part of the mine is in progress. Drifts and cross¬ 
cuts probably aggregate 2,500 to 3,000 feet. 
The principal rock of the mine is latite-phonolite, but phonolite breccia is 
reached on level 2, 350 feet south of the shaft. Ninety feet south of the shaft on 
this level the basalt dike from the Deadwood No. 2 crosses the north-south drift. 
Only one vein of any importance has been encountered. It has a north-south 
course, dips steeply to the west and lies just east of the shaft. It consists of an 
oxidized and shattered zone 2 to 5 feet wide in latite-phonolite. Fifty feet south 
of the shaft a body of oxidized ore was encountered which was shipped as broken, 
and contained II to 2 ounces per ton. A stope on this ore shoot is 4 to 5 feet wide, 
35 feet long, and 100 feet high. The southern limit of the shoot is the basalt dike, 
which is also being stoped near the vein. This was the only shoot that had been 
found in the mine at the time of visit. 
VINDICATOR RODE SYSTEM. 
The depression between Bull Hill and Bull Cliff contains one of the most 
important and productive lode systems of the camp. While the general country 
rock is breccia showing the usual alteration, there are in this vicinity two large 
intrusive masses, the northern one consisting of latite-phonolite and the southern 
one of syenite. A smaller intrusion of latite-phonolite adjoins the syenite on the 
south near the town of Goldfield. The mining developments show that these are 
not flat masses, but rather deep batholiths extending to the greatest depths yet 
attained. The syenite borders in places with sharp contacts against latite-phonolite, 
while other exposures present all kinds of transitions between the two rocks. There 
are few basic dikes and few phonolite dikes in this vicinity; none of them is of 
economic importance. 
The lode system is traceable for nearly a mile, the individual veins diverging 
slightly northward, as is well shown in the Vindicator and Golden Cycle mines. 
The dip is usually very steep. The following mines, taken from north to south, are 
located on this system: Shurtloff, Findley, Hull City, Lillie, Ahndicator, Christmas, 
and Golden Cycle. All of them are producing mines of importance except the 
Christmas and the Lillie, on which little work is now being done. The total produc¬ 
tion of the system is approximately $10,000,000. 
A depth of 1,500 feet is attained in the Lillie, 1,400 feet in the Findley, 1,200 
feet in the Vindicator, "and 1,000 feet in the Golden Cycle. 
