242 Tlic American Geologist. Octobor, i899 
above No. 9, and much iron pyrites and other minerals below 
that stratum. Yet it has had nothing to do with the presence of 
the metallic sulphides which so highly impregnate the lower 
strata cut by the shaft. The limestone layer, No. 9, is one of 
the regular strata of the brown shale series, and the "gold 
ore" may be said to occur in the form of a "blanket vein" 
rather than of a vertical or fissure vein. The layer of country- 
rock contains irregularly disseminated masses of rose quartz 
of the size of a walnut up to that of an apple or larger, and 
it is these quartz-filled cavities which carry the gold. An 
assay made from a piece of one of these quartz masses, on 
Nov. 4, 1897, by E. E. Burlingame & Co. of Denver, Colo., 
was returned as : Gold oz. per ton, 4.04 oz. valued at $80.80, 
(being at rate of $20.00 per oz. of gold) ; and a trace of silver. 
I see no particular reasons for discrediting the above returns 
as, from acquaintance with the parties interested, I do not be- 
lieve any effort has been made to "salt" a mine. I have 
myself seen in the material from the mine, iron pyrites, zinc 
blende, galenite, native copper, quartz, calc spar, and free 
gold or the best imitation of it that I have ever encountered. 
From the material thrown out of the shaft, and from out- 
crops farther down the hill-side, I recognize the first two 
strata of the above section as "drift ;" Nos. 3 to 5, Cincinnati 
or Hudson River shales ; Nos. 6 to 14 inclusive, Utica shales ; 
and the remainder. "Everts limestone," a local designation of 
the upper portion of the Galena series. The black shale, No. 
7, is very characteristic of the Utica in this northwestern por- 
tion of Illinois. Under it is a curious combination or alter- 
nation of thin layers of fine conglomerate or coarse sandstone, 
impure limestone, brown clay and layers of pyrites. I have 
long thought I detected evidence of an old soil layer or land 
surface at this horizon. However, the few feet of strata which 
make up this peculiar portion of the Utica series are always 
highly mineralized ; indeed, in the gutters below the Eleroy 
"gold-mine," there are outcropping thin layers of coarse sand- 
stone in which the cementing material is pure iron pyrites. 
About a mile and a half west of Pearl City, and six miles 
southwest of the Eleroy mine, there is another of the so-called 
"gold mines" of this county. The several shafts here dug 
