16 CONTRIBUTIONS TO MINERALOGY. [bull. 262 
the movement and had filled the small openings and dislocations in thi 
shale caused by this very recent disturbance. It was reported tha 
some of the best nests of ore had been found in "slide rock," i. e. 
rock which had slipped to some extent down the slope; but I wa 
unable to verify this statement further than is indicated in the pre 
ceding description. There can be little doubt that the deposits of car 
notite on La Sal Creek are not only very superficial in character bu 
very recent in age. 
ROC CREEK DEPOSIT. 
The principal claim is the Copper Prince, owned by J. R. Duling 
on the north side of Roc Creek, 3 or 4 miles above its mouth, and nea 
the foot of the Miller trail to Paradox. It is reached by this trail fron 
Paradox Valley, or by trail from Hydraulic on the Dolores River 
This deposit is in the La Plata sandstone, according to Doctor Spen 
cer's observations, and has been more extensively exploited than an; 
other seen. The sandstone, which at this point is nearly horizontal 
is cut by an east- west fault, the fault plane dipping north at about 7(> c 
The amount and character of the throw could not be determined. I 
is probably less than 50 feet. The carnotite occurs in the hanging wai 
of the fissure as small irregular branches in a loose mass of crusher 
sandstone and also as an impregnation of some of the firmer portion 
of the bed. No roscoelite was seen. Several small tunnels have bee 
run in on the hanging wall side of the fissure (which itself carries r 
vein or ore-body), but they had been securely closed by planking, an 
no examination of their inner ends could be made. I am thus unab 
to tell what changes the deposit would show if it could be folio we 
inward from the surface. A few hundred pounds of picked carnoti 
ore has been shipped from this claim and is reported to have sold f< 
$1.25 a pound in Denver. This deposit is similar in character to othe 
examined, except that in this case a well-defined fault has provided: 
zone of crushed and porous rock in the hanging wall, along whi 
impregnation could take place. A few hundred feet farther west tt 
crushed sandstone adjoining the fault has been impregnated wi 
cupriferous solutions and is spotted with stains of the blue and gre 
carbonates of copper. 
OTHER DEPOSITS. 
It is known that several carnotite claims have been located 
Gypsum Valley in what is known as the Disappointment distriij 
The impregnated sandstone is said to cap a hill and to constitute 
extensive deposit, but it was not visited. Carnotite is also repor 
from the Blue Mountain district, but I have no personal knowledge 
these occurrences. It seems highly probable that the material \ 
be found widely distributed in the Mesozoic sandstones of west 
Colorado and eastern Utah, although perhaps nowhere in very ext 
sive bodies. 
