354 GEOLOGY AND GOLD DEPOSITS OF THE CRIPPLE CREEK DISTRICT. 
down to the bottom level. The extreme upper limit of the ore seems to be deter¬ 
mined, at least in part, by a zone of nearly horizontal Assuring containing soft, 
crushed granite or gouge and some pyrite. At those points where the pay shoot 
follows fissures crossing the plane of the C. K. & N. lode it contains ore of the same 
character as in the C. K. & N. lode proper, but this ore is usually accompanied by a 
fissure containing soft gouge and pyrite (fig. 39, p. 350). Such soft material never 
constitutes pay ore. Some of the best ore on the C. K. & N. lode occurs near its 
intersection with the El Paso lode. 
The old stopes on the El Paso lode near the old shaft are no longer worked, and 
no observations could be made on the occurrence of this ore. The pay shoot or 
shoots in this part of the lode appear to have had a total length of about 500 feet 
and come to an end near the new level 1, or approximately 200 feet below the sur¬ 
face. At this depth the lode shows a little oxidation, but only along some of the 
more open fissures of the sheeted zone. On level 2 the El Paso sheeted zone, while 
fairly distinct, contains no ore south of the main shaft. The principal pay shoot in 
this lode lies northeast of the main shaft, chiefly in the acute angle formed by the 
intersection of the lode with the El Paso dike. This ore formed an irregular mass, 
which extended from a point about 70 feet above level 1 almost to level 3. Near 
level 1 the pay shoot is only a few inches wide, and is a sheeted zone in granite at 
the under cont act of the El Paso dike. The ore occurs as calaverite, mainly in the 
medial vugs of a veinlet of fluorite less than an inch wide. Above the level this 
veinlet finally pinches out. Below the level the main fissure diverges from the pho¬ 
nolite, and the granite between it and the dike is much fissured and mineralized, con¬ 
stituting on level 2 an ore body 40 feet wide. The irregularity of the Assuring at this 
point appears to be connected with an irregular sill-like offshoot from the phonolite 
dike into the granite and the presence in the latter rock of some streaks or inclu¬ 
sions of schist. The El Paso lode itself also splits into a number of fairly regular 
divergent sheeted zones as it approaches the under side of the dike. Granite, phono¬ 
lite sill, and schist lenses are all traversed by reticulating fissures containing quartz 
and calaverite. Below level 2 the Assuring becomes less pronounced, the ore con¬ 
tracts, and on level 3 there is practically no ore where the El Paso lode and El Paso 
dike meet. The ore body has, roughly speaking, the form of a flattened ellipsoid 
lying against the under side of the phonolite dike, its longest axis pitching to the 
northeast with the general line of intersection of lode and dike. The ellipsoid has 
its greatest thickness of 40 feet near level 2, about 200 feet northeast of the main 
shaft, and decreases peripherally to zero. It is far from regular, however, as it 
contains several horses of unmineralized country rock, and the ore often extends 
for short distances along some of the more definite fissure zones. 
Although the main contact between the granite and the Beacon Hill phonolite 
plug is not generally mineralized, it carries bodies of ore at several points, notably in 
the now idle workings of the Australia tunnel and Little May mine. In the El 
Paso workings some ore occurs along the contact on level 2, but only in one or more 
irregular sills in the granite, which connect with the main phonolite mass. There 
has been slight movement along the general contact since the phonolite solidified, 
and the sills are irregularly fissured. In one stope visited the sill was about 6 feet 
in thickness and contained ore for a maximum distance of 15 feet from the main 
contact. The ore occurs as calaverite in the minute fissures in the phonolite. 
