32 NEW YORK STATE MUSEUM 



New York has a leading place in the gypsum industry, both 

 from the standpoint of the mine product and of the manufacture 

 of gypsum plasters. Its position in the calcined plaster trade is 

 even more important than the output of rock gypsum would indi- 

 cate, since in recent years large quantities of crude rock have 

 been imported by local mills for calcination. Most of this material 

 comes from the Maritime provinces of Canada, under the moderate 

 transporation rates that ordinarily obtain for water shipments, and 

 is used by calcining plants situated on the lower Hudson and in the 

 environs of New York City. , Nova Scotia is the source of most 

 of the imported rock; it possesses large deposits that are conveni- 

 ently situated for reaching the seaboard markets. In the interior 

 of the State the calcining plants are mostly operated in connection 

 with the local mines, from which they obtain all their crude 

 material. 



The production in 1915 was reported from four counties — 

 Onondaga, Monroe, Genesee and Erie — the same that have yielded 

 most of the supply in recent years. The deposits are not confined 

 to these counties, however, since they outcrop at intervals all the 

 way from Madison county on the east to the Niagara river, and 

 extend southward under cover of rock for indefinite distances. The 

 present mine localities possess advantages either as to quality of. 

 product or for economical extraction and marketing which have led 

 to the concentration of operations in their vicinity. 



The most easterly point at which beds of workable dimensions 

 occur is in Madison county. Here they take the form of rather 

 small lenses, not over 4 or 5 feet thick in most instances, though 

 occasionally of greater thickness and extent, and consist of gypsum 

 intermixed with argillaceous material and the carbonates of lime 

 and magnesia. On the average the rock from this section carries 

 about 70-75 per cent gypsum and is drab or gray in color. It has 

 been employed quite extensively for agricultural plaster, and there 

 are a number of quarries along the line of the Lehigh Valley Rail- 

 road to the south of Canastota, and also farther west along the Erie 

 canal between Chittenango and Sullivan, which were worked quite 

 extensively up to 15 or 20 years ago. Of late the substitution of 

 limestone for gypsum in agriculture has restricted the market for 

 the output of quarries of this section, and no active work has been 

 under way for several years. 



In Onondaga county around Fayetteville and Jamesville occur 

 beds of large size up to 50 or 60 feet thick that are worked in a 

 small way, mainly for agricultural plaster and for use in portland 



