MfNHS OF GOLD HILL. 
303 
In the Midget mine the ore in the Midget lode nearly all occurs above level 6 
and is all partly oxidized. Calaverite, free gold, and fluorite are said to be charac¬ 
teristic constituents. As seen just above level 6, this ore consists of breccia con¬ 
taining small disseminated crystals of pvrite and traversed by minute irregular 
veinlets of fluorite. Some of the veinlets are oxidized and show a little rusty gold. 
No calaverite was seen, but it is said to be sometimes visible. The ore of that nart 
of the Bonanza King lode which is in breccia is similar to the ore of the Midget 
lode. In the gneiss, however, the ore is distinguished from the country rock by 
the presence of tiny veinlets of pyrite. These veinlets sometimes contain a little 
quartz, feldspar, and fluorite, but so far as observed no visible calaverite. That 
calaverite or sylvanite is really present with the pyrite in the little veinlets is clearly 
shown, however, by the action of oxidation, which within 30 or 40 feet of the sur¬ 
face has changed the telluride to visible specks of dull native gold, while the pyrite 
is unaltered. 
The ore of the Conundrum lode consists of mineralized “basalt.” The rock 
is traversed by numerous narrow fissures, sometimes reticulating, but usually 
showing general parallelism with the dike walls. These little fissures are filled or 
partly filled, sometimes with purple fluorite, sometimes with quartz, and some¬ 
times with both minerals together, giving the rock a handed appearance. These 
gangue minerals are not always confined to the fissures, but sometimes permeate 
the altered basalt between the distinct fractures. 
As seen under the microscope, the “basalt” between the veinlets is thickly 
sprinkled with minute pyritohedral crystals of pyrite and with granules of sec¬ 
ondary quartz. These lie in an exceedingly fine-grained and obscurely crystalline 
aggregate of uncertain composition. It appears to be partly quartz, partly feld¬ 
spar, and partly some isotropic material, but the texture of the material is too 
fine for the microscopical determination of its constituents. It reveals no trace of 
the original igneous texture of the rock. 
The gold occurs as calaverite associated with the quartz and fluorite and with 
pyrite. The ore, however, is often oxidized even below level 9 of the Midget or 
level 5 of the Conundrum, and the calaverite changed to native gold. Little 
specks of galena and sphalerite are common in the Conundrum dike, usually accom¬ 
panying the gold ore. These minerals appear to have been deposited at least in 
part by replacement of the basalt and sometimes form bunches or lenses several 
feet long and 5 or 6 inches in thickness. This galena and sphalerite ore frequently 
contains 2 or 3 ounces of gold and about the same quantity of silver per ton. Galena 
and sphalerite are not confined to the Conundrum lode, but occur also in the Midget 
mine in the Bonanza King lode as lenticular masses a foot or so in thickness, replac¬ 
ing fissured gneiss. On level 8 this galena and sphalerite are associated with the 
usual calaverite gold ore and barely pays to mine. In the Moon-Anchor mine 
galena, sphalerite, and pyrite, associated with quartz, fluorite, and rhodochrosite, 
constitute the Lead vein, in breccia. 
The ore in gneiss in the northern part of level 6 of the Conundrum consists of 
calaverite, often beautifully crystallized, occurring in the vugs of quartz-fluorite 
veinlets. 
