60 LAKAMIE BASIN, WYOMING. 
USE. 
Shipments of bentonite from the Laramie Basin began in 1888, 
when several carloads were used by eastern firms in the manu- 
facture of " hoof packing, " a dressing or poultice for the inflamed 
hoofs of horses. Its chief use, however, is to give body and weight in 
the manufacture of paper, and practically the whole output of the clay 
for the last few years has been taken by a paper mill in Denver, Colo. 
Other uses are in antiphlogistine, a proprietary remedial dressing, and 
as an adulterant in candies and drugs. Though highly plastic it is 
unsuitable for the manufacture of fire-clay products on account of its 
ready fusibility. It is a good retarder for use with the hard cement 
plasters. Its high absorption of glycerine as compared to diatoma- 
ceous earth suggests its substitution for that material in the manu- 
facture of dynamite. 
DESCRIPTIONS OF LOCALITIES. 
Bock Creek region. — The bentonite mines in the Rock Creek region 
lie at intervals along the outcrop of the Benton formation for a dis- 
tance of 20 miles. The bed is persistent throughout that distance, 
although in places it is covered by talus or wash. The principal pro- 
duction of bentonite in the Laramie Basin has been from the Taylor 
mine, in the NW. \ SE. \ sec. 30, T. 22 N., R. 75 W., about a quarter 
of a mile north of old Rock Creek station, now Rock Creek post-office. 
This mine was opened in 1888. The bentonite outcrops on the slopes 
of the hill with a thickness of 4 to 5 feet, and dips to the south at an 
angle of 4° or 5°, the same angle as the slope of the hill, so that the 
bed is exposed over several acres. The top, consisting of a few inches 
of weathered debris, is stripped off and the bentonite loaded onto 
wagons and hauled to Wilcox, the nearest railway station, a distance 
of 6 miles. It is shipped loose in box cars, either in lumps as it natu- 
rally comes from the pit or as the fine loose powder which results from 
weathering. 
In 1897 a pit was opened about 3 miles southeast of the Taylor 
mine at Linscott's claim, in the NW. \ sec. 17, T. 21 N., R. 75 W., 
near the old line of the Union Pacific Railroad. About 20 carloads 
were shipped from this place, exhausting the readily accessible supply. 
Another pit was then opened in the SE. \ NE. \ sec. 14, T. 22 N., 
R. 76 W., on the north side of Rock Creek, from which about 100 car- 
loads have been shipped. The thickness and relations are analogous 
to those at the Taylor mine. 
A claim owned by the Cassa Mining Company is located in the N. \ 
sec. 10, T. 22 N., R. 76 W., but only samples have been shipped. 
The claim is a mile in length, and the clay presents the same features 
as at the other localities. 
