THE MINING AND QUARRY INDUSTRY I912 &7 



The Rylestone quarries. The Rylestone quarries, which were 

 closed at the time of the writer's visit, lie a mile or so south of 

 the main belt on a separate lead. They are situated on the side of 

 a low hill and are not worked below the surface. The marble is a 

 coarse medium to light stone, in which the blue and white are 

 equally mixed. It lacks the uniformity of texture exhibited by 

 the marble elsewhere and is subject to considerable loss in quarry- 

 ing by reason of vugs that are apt to be disclosed in the midst of 

 an otherwise sound block. These vugs range from very minute 

 cavities lined with crystallized minerals to those a foot or two in 

 length. Calcite, marcasite and brown tourmaline are the more 

 common minerals found in them. 



The quarry face is about 100 feet long at the base and 50 feet 

 high. In the last operations, the stone has been quarried away by 

 blasting. The product was sawed in a mill nearby equipped with 

 eight gangs. 



There are a number of quarry openings on the main belt which 

 have been idle for some time, such as the Callahan quarry on the 

 northeast end, the Sullivan quarry, near the St Lawrence quarries, 

 and the quarry of the former Whitney Marble Co., on the south- 

 west, near the property of the Northern New York Marble 

 Company. 



Southeastern New York. Crystalline limestone is found in the 

 Highlands and the bordering metamorphosed area to the north and 

 south. It is specially prominent on the east side of the Hudson, 

 where it underlies many of the north-south stream valleys of West- 

 chester, Putnam and eastern Dutchess counties. It is associated 

 with schists, quartzites and thinly bedded gneisses, the whole series 

 of interfolded metamorphosed sediments bearing much resemblance 

 to the Grenville series of the Adirondacks. There is some doubt, 

 however, as to the stratigraphic position that should be assigned 

 to the limestone, if indeed it is to be regarded as an essentially 

 continuous formation throughout the area. 



In Westchester county the limestone is coarsely crystalline, white 

 and usually dolomitic, but varying considerably in its magnesia 

 content. The name " Inwood " limestone was first applied to it by 

 F. J. H. Merrill, who later advocated the view of the general 

 equivalence of the limestones in this section with those of western 

 New England and withdrew that name in favor of the prior term 

 " Stockbridge dolomite." 



In the northern section in eastern Dutchess county, the lime- 



