128 ECONOMIC GEOLOGY OF AMITY QUADRANGLE, PA. 
PROSPERITY LIMESTONE. 
The Prosperity limestone is a bed not mentioned in the old Pennsyl- 
vania reports, and it was probably confused with the Upper Washing- 
ton bed, to which it is very similar in appearance. The name "Pros- 
perity" has been suggested by Mr. M. J. Munn from the village of that 
name in Washington County. The horizon of this bed is 100 to 180 
feet above that of the Upper Washington, and the limestone outcrops 
at many points in South Strabane and Amwell townships as a hard, 
dark blue-gray to nearly black rock. 
In thickness the Prosperity limestone is supposed to reach in places 
20 feet. So far as known, it has not been tested, but from its compact 
nature and considerable thicknesss it would seem to be of probable 
future value, although in this quadrangle it is not very accessible. 
SANDSTONE. 
The sandstones of the Amity quadrangle are in general shaly and of 
poor quality, but a number of beds seem to offer stone of possible 
value. 
PITTSBURG SANDSTON E. 
This name is applied to a bed of sands! one ranging up to 70 feet in 
thickness, which in many places overlies the Pittsburg coal. Whore 
best developed it is coarse and friable. It can be seen at several points 
on Chartiers and Peters creeks, but is there poorly developed. On 
Fish pot Run, on the edge of the quadrangle near its southeast corner, 
the sandstone is well exposed in cliffs which rise above the Pittsburg 
coal to a height of nearly 100 feet (PL VI 1 1 A). So far as known, the 
Pittsburg sandstone has not been utilized. 
V. iTNESBURQ SANDSTONE. 
The Waynesburg is a coarse, flaggy, much cross-bedded sandstone, 
from 20 to 70 feet thick, resting on the Waynesburg coal or separated 
from it by a few feet of shale. Its color is usually buiT-yellow to light 
gray. The name is derived from the town of Waynesburg, near which 
the rock is finely exposed. This is one of the most conspicuous and 
persistent sandstones in the upper portion of the Carboniferous system, 
and furnishes a good guide to the position of the Waynesburg coal. 
In the Amity quadrangle the Waynesburg sandstone is probably 
most prominent on Little Tenmile Creek, in the vicinity of Lone Pine, 
where it crops out in 30-foot cliffs directly above the Waynesburg coal. 
At this locality it forms a flat terrace on which part of the village has 
been built, about 40 feet above the creek. The terrace and the char- 
acter of the sandstone are illustrated in PL VIII, B. 
The sandstone is also finely exposed on Little Chartiers Creek 
between the National pike and Linden, where it can be traced along 
