yo NEW YORK STATE MUSEUM 



Bodies of practically pure serpentine of considerable extent are 

 found on Staten Island and in Westchester county near Rye; they 

 represent intrusions of basic igneous rocks whose minerals, chiefly 

 pyroxene and olivine, have subsequently changed to serpentine. 

 They are not important for quarry purposes, owing to the frequency 

 of fissures and joints and the rather somber color of the exposed 

 part of the masses. 



The microcry stall ine or subcrystalline limestones that are some- 

 times sold as marbles include members of the regularly bedded 

 unmetamorphosed Paleozoic limestones, which locally show quali- 

 ties of color and polish that make them desirable for decorative 

 purposes. They range from dense granular varieties to those 

 having a more or less well-developed crystalline texture and are 

 often fossiliferous. Inasmuch as they have never been subjected 

 to regional compression or been buried in the earth deep enough 

 to become heated, the crystalline texture, when present, may be 

 ascribed to the work of ground waters. These circulate through 

 the mass, taking the carbonates of lime and magnesia into solution, 

 and redeposit them in crystalline form. Originally, the limestones 

 were accumulations of lime-secreting fossils or granular precipi- 

 tates, for the most part of marine origin. Some of the localities 

 where these unmetamorphic marbles occur are on the west shore of 

 Lake Champlain, around Plattsburg and Chazy (Chazy limestone), 

 Glens Falls (Trenton limestone) and Becraft and Catskill (Becraft 

 limestone). 



Production. The marble quarries reported a very poor business 

 in 191 5, the output amounting to about one-half that of the average 

 for previous years. The depression affected both building and 

 monumental quarries. The number of firms reporting a production 

 was seven, distributed among Dutchess and Westchester counties in 

 southeastern New York and St Lawrence and Warren counties 

 in the Adirondack region. In the Gouverneur district the St Law- 

 rence Marble Quarries and the Gouverneur Marble Co. alone were 

 active. The Northern New York Marble Co. of that place went 

 out of business. The quarries of the South Dover Marble Co. at 

 Wingdale were worked as heretofore, though on a reduced scale. 

 In Westchester county the old " Prison " quarry at Ossining was 

 reopened for the purpose of getting out dimension stone for the 

 remodeling of the State Hall at Albany, which is constructed of 

 marble from this quarry. 



The production of marble altogether was valued at $120,447 

 against $230,242 in 1914 and $252,292 in 1913. Of the product, 



