I 
MINES OF GOLD HILL. 807 
intrusive rock extends much farther northeast than it does on the surface. It is 
the prevailing rock in the crosscuts which extend from the Mint shaft under the 
abandoned Keystone shaft, which is 150 feet east of the Mint. 
LODE SYSTEMS. 
The principal lode is the Pointer, which strikes N. 33° E. and dips 80° NW. 
The Pointer and Mint shafts are approximately on the line of the lode. In the 
Pointer workings the lode is very close to the contact between the syenite and 
breccia. It is in syenite down, to level 7, and that level practically marks the 
contact. About halfway between the Pointer and Mint shafts the lode passes 
through a phonolite dike. Northeast of the dike the Pointer lode is in breccia, 
and is less distinct than in the Pointer mine. There are at least two other north¬ 
east-southwest lodes in these workings. One of these is the New vein, which has 
been exploited in some short drifts northwest of the Mint shaft; the other is the 
Keystone lode, southeast of the Mint shaft. Neither of these has been contin¬ 
uously followed for over 200 feet on any level. They have generally northwesterly 
dips, but are branching and rather irregular fissure zones’, apparently of no great 
persistency. The New vein is in breccia and the Keystone vein, as seen in levels 
accessible from the Mint shaft, is in syenite. The latter lode probably passes into 
breccia, however, near the surface. 
CHARACTER OF ORE. 
No ore was to be seen in the Mint mine at the time of visit. The ore of the 
Pointer lode contains a gold-silver telluride, probably sylvanite, in a quartz and 
fluorite gangue. Certain portions of the lode contain galena, sphalerite, and 
tetrahedrite, often associated with rhodochrosite. The quartz, fluorite, and sylvan¬ 
ite appear to have been deposited, as a rule, after the formation of the other vein 
minerals named. The ore containing tetrahedrite and galena is usually rich in 
silver, which appears to occur chiefly in the tetrahedrite. Some of this ore is 
reported to contain over 500 ounces of silver per ton, and Stevens 0 records a state¬ 
ment of the superintendent of the Accident mine, to the effect that about 1,000 
pounds of gray copper ore from that mine contained 2,500 ounces of silver and 25 
ounces of gold. The ore being shipped by lessees from the Pointer mine at the time 
of visit was running about $53 per ton, with silver and gold present in about equal 
proportion by weight. 
PAY SHOOTS AND LODE STRUCTURE. 
The productive portion of the Pointer lode is a narrow sheeted zone in syenite, 
with a pay streak rarely exceeding 5 inches in width. The main pay shoot extends 
from a point a few feet above level 4 of the Pointer mine, or about 300 feet below 
the surface, to an unknown distance below level 7. Its maximum length of 400 
feet is attained on level 5. On level 7 the shoot is a little over 100 feet in length, 
and it is doubtful whether it continues far below the level. On the northeast the 
ore ends at the phonolite dike, the lode being of no value in the dike or in the 
a Basaltic zones as guides to ore deposits in the Cripple Creek district, Colorado: Trans. Am. Inst. Min. Eng., vol. 33, 
1903, p. 698. 
