MINERAL RESOURCES OF THE STATE OF NEW YORK 47 



CLAY MATERIALS 



A wide assortment of clay wares is made in New York State. 

 The list of products includes common and ornamental building 

 brick, terra cotta, hollow blocks, fireproofing, paving brick, fire 

 brick, drain tile and sewer pipe, and various grades of pottery. The 

 manufacture of building materials is especially important and is 

 carried on in nearly every section, favored by extensive deposits of 

 clay suitable for the purpose as well as by unrivalled market facilities. 

 This branch of the industry enjoyed great prosperity in the period 

 from about 1895 to 1910 when building operations were notably 

 active throughout the State; but the use of clay materials seems 

 destined to attain even greater proportion in the future by reason of 

 their relative cheapness, their durability and the ease with which they 

 may be adapted to various architectural requirements. 



The finer grades of clay wares are now being made in considerable 

 quantities. Their manufacture, however, is not dependent on local 

 materials for the most part. In contrast with the other States along 

 the Atlantic seaboard to the south, New York possesses only scanty 

 resources of the high-grade clays suitable for porcelain and white 

 wares. Such deposits occur here and there, but hardly in workable 

 quantities. The lack of kaolin and white clays may be ascribed to 

 the work of the glacial ice which in the Pleistocene swept over practi- 

 cally all of the State, carrying away the deposits of residual clays 

 and replacing them with beds of bowlder clay and water-laid mixed 

 clays. 



OCCURRENCE AND CHARACTER OF CLAYS 



The distribution of clays in New York, as well as their character, 

 uses and industrial development, has been described at length in 

 the report by Professor H. Ries, " Clays of New York " published as 

 Bulletin 35 of the New York State Museum. The following resume 

 is based largely on data contained in that report. 



The soft plastic clays, as distinguished from shale, have accumulated 

 during the more recent geologic ages, ranging from the Cretaceous 

 period to the present. The time of most widespread clay deposition 

 was the late Pleistocene when practically all of the clays of the main- 

 land were laid down. Cretaceous clays have a limited distribution on 

 Long Island and Staten Island, and a few deposits on the north 

 shore of Long Island have been referred to the Tertiary period. 



The Pleistocene deposits were formed under various conditions, 

 but in most instances as the result of glacial action or of the retreat 

 of the ice sheet from the gradual melting of the southern margin. 



