THE MINING AND QUARRY INDUSTRY I915 55 



The most important deposits from a commercial standpoint are 

 those found on the northern shores of Long Island. These are 

 dredged from shallow waters or excavated along the exposed 

 beaches, and prepared by screening. Enormous quantities are 

 taken each year from the northern shores of the island within the 

 limits of Nassau county. The sand is shipped in barges to New 

 York and the environs for use in buildings, street work, etc. 



Some of the lake beaches in the interior of the State afford 

 excellent building sands. Oneida lake is bordered by extensive 

 sand beaches from which quartz sands, some of high quality, are 

 obtained. 



The output of building sand in 1915 was returned as 4,127,508 

 cubic yards, worth $1,185,812, a little over the output reported for 

 the two preceding years. The output included some sand used for 

 water filtration, which is obtained from the same beds as building 

 sand. 



Molding sand. The Hudson valley from Fort Edward south to 

 Poughkeepsie contains extensive areas of fine sands which repre- 

 sent the last deposits formed in glacial Lake Albany. 1 They overlie 

 the blue and yellow clays, deposited during the same period of flood 

 waters, but have a rather variable vertical distribution owing to 

 effects of wind erosion which in places has swept them away to 

 heap them up elsewhere in dunes. The sand normally contains 

 considerable shale, but through weathering the shale is resolved 

 into clay with the release of some iron. The weathering is also 

 marked by a change of color, from grayish to yellow. This yellow 

 weathered sand is a pure quartz sand and is remarkable for the 

 angularity and even size of the particles. It usually possesses also 

 a fine grain. The combination of qualities makes it a valuable 

 molding sand, especially for small castings like stove-plate and 

 other iron work which require a smooth surface. 



The business of excavating and shipping the sand of this dis- 

 trict is extensive and is carried on by a number of concerns, each 

 of which usually has several banks under operation so as to be in a 

 position to supply the various grades in demand. The output in 

 recent years has ranged from 300,000 to 500,000 short tons. In 

 191 5 it amounted to 454,511 short tons valued at $415,073, which 

 represented a large gain over the product reported in 1914 when 

 the industry felt the effects of the general depression in the metal 

 trades. 



1 A detailed account of the molding sands of this region will be found in a 

 paper by D. H. Newland in Trans. Amer. Foundrymen's Association, v. 24. 

 1914. 



