MINERAL RESOURCES OF THE STATE OF NEW YORK 275 



the straight, even grained, well bonded, quartz sandstone, rank 

 with the best freestones of the country. Examples of its architec- 

 tural use may be seen in the larger cities of the State — Buffalo, 

 Rochester, Syracuse, New York — and also throughout the middle 

 west; while it has had equal favor for street work. It is quite 

 resistent to weather and the well bonded sorts do not readily crack 

 or " open " if laid on edge. In recent years the demand for archi- 

 tectural stone has diminished to such an extent that the product 

 now sold for that purpose is a small item in the total ; paving blocks, 

 cross-walks and curbstone being the principal kinds produced. 



The Medina sandstone is typically a quartz sandstone with a 

 ferruginous or siliceous bond. The grain is mediimi to coarse. 

 Cross-bedding is not very common, the lamination being usually 

 straight. The individual beds range up to 5 or 6 feet thick. Thin 

 argillaceous sandstones are also found in the series, as a gradation 

 to the shales which lie below the coarser sediments. A parting of 

 red shale may also lie between the sandstone layers and is known 

 as " red horse." In depth, as the level of ground water is reached, 

 pyrite is likely to appear in knots within the stone and as films 

 upon the joint surfaces. The color is light gray, pink, or variegated 

 in the two tints. The gray stone is locally called " white " Medina. 

 In limited amount occurs a reddish-brown variety which is in most 

 demand for building purposes. 



The Medina formation extends along the southern shore of Lake 

 Ontario in a belt about 10 miles wide. It contains an assemblage 

 of shales and sandstones altogether about 1200 feet thick in their 

 extreme development. The sandstones in which the quarries are 

 located lie in the upper 150 feet of the formation and usually just 

 north of the ridge which marks the outcrop of the Niagara dolomite. 

 The area underlain by the beds is quite flat and the quarries are in 

 the form of pits or trenches, with 5 to 15 feet of glacial cover and 

 20 to 30 feet of rock face. It is not possible as a rule to carry the 

 excavations deeper than this on account of the ground water which 

 lies close to the surface in most places. The selection of quarry 

 sites has been made with reference to transportation facilities supplied 

 by the canal and railroad lines, most of the present quarries lying 

 along the old Erie canal. 



The principal operations are carried on in Niagara and Orleans 

 counties in the stretch from Lewiston to Holly. In the Niagara 

 section the output is represented largely by light gray stone which 

 is obtained from near the base of the quarry face. There has been 

 little demand of late years for this variety as building stone. The 



