hansome] DEPOSITS OF RED MOUNTAIN REGION. 245 
from this claim, the ore occurring in replacement bunches in the 
limestone alongside the fault. The ore is associated with a soft, 
black alteration product or residue of the limestone. Between the 
Maud S. and the Mono fissures is a third fault exposed on the Mono 
tunnel, of variable northeasterly strike, dipping southeast at about 
70°. Here also the andesitic tuff or breccia is brought down on the 
southeasl so as to be in iuxtaposition with the limestone. The fault 
is well shown in a long drift run on it to the southwest. The fissure 
contains soft gouge and shows slickensides, but is about destitute 
of ore. 
The Brooklyn tunnel, 200 feet below the Mono tunnel, enters in 
limestone, which is probably over 200 feet thick in this gulch. The 
tunnel has several branches, the longest about 800 feet in length. It 
cuts through at least two large masses of crumbling iron pyrite, 
formed by replacement of the limestone. These masses are bounded 
on the southeast by a northeast fault plane, which brings them 
against a down thrown mass of andesitic breccia. This fault is sup- 
posed to be the one already described between the Maud S. and 
Mono fissures. The only one of these pyrite masses which could be 
reached in !!)()<> is a1 least 6 feci in thickness (the height of the drift), 
and probably considerably more. Northwest of the fault it extends 
irregularly into the limestone for over LOO feet. Northwest of these 
masses of pyrite is a long northeast drift, which appears to follow a 
fault for most of its course. On the southeast side of the drift is 
limestone with hunches of iron pyrite. On the northwest side is an 
irregularly laminated and much disturbed quartzite, which may prob- 
ably he the "lower quartzite" of Kedzie. The general strike of this 
laminated quartzite, i. e., of the laminae, is about northeast. The 
general dip is northwest, hut exceedingly variable. r l nis quartzite 
belongs presumably below the limestone, but whether it is the same 
as the massive quartzite at the Saratoga Mill or is a younger quartzite 
not there seen, and perhaps of Devonian or Silurian age, is not at pres- 
ent known. 
Jay Eyt St < mint . This also is a prospect situated in Parole Gulch, 
south of the Maud S. A shaft was formerly sunk on a heavy lode or 
bunch of pyrite, associated in this case with a little quartz gangue. 
No pay ore was ever found in this shaft. Subsequently a tunnel run 
in just west of the shaft cut a lode which in places carried tetrahedrite, 
pyrite, and chalcopyrite up to 4 feet in width. The ore occurred in 
lenses connected by a ban-en seam of clay gouge in soft decomposed 
andesitic tuff-breccia, and the mine never paid steadily. The tetra- 
hedrite sometimes carried 400 ounces of silver per ton. The bodies 
of pyrite cut in the original shaft are quite probably part of the Mono 
lode. But parallel fault fissures of southeasterly dip and normal 
heave are here so common, however, that identification of any single 
one is almost impossible. 
