144 NEW YORK STATE MUSEUM 



Westchester counties. The aggregate value of the output reported 

 by 14 producers amounted to $774,557, divided as follows : building 

 marble, rough and dressed, $571,810; monumental, rough and 

 dressed, $177,557 5 other kinds, $25,190. Most of the marble used 

 for building purposes came from southeastern New York, the out- 

 put of this region being valued at $464,24-7. The remainder was 

 supplied from Plattsburg and Gouverneur. St Lawrence county 

 reported a total production valued at $265,722, of which $173,557 

 represented the value of monumental marble. 



The production for 1905 was probably the largest ever made in 

 the State. It exceeded that of the previous year by over 60 per 

 cent. 



Sandstone 



BY C. A. HARTNAGEL 



Sandstones include the sedimentary rocks which consist of grains 

 of sand bound together by some cementing material. The sand 

 grains are derived from preexisting rocks, either igneous or sedi- 

 mentary, and represent the more resistant constituents that were left 

 in the form of sand when the rocks underwent disintegration 

 through the various agencies of weathering and erosion. 



The form or shape of the grains may be angular, as in the river- 

 derived sands, or they may be more or less rounded, as is the case 

 with wind-blown sands and those which before deposition and con- 

 solidation have been rolled about by wave action. The texture 

 of sandstones may be fine, medium or coarse, depending upon the 

 size of the grains, which ranges from dustlike particles up to 

 pebbles an inch or more in diameter. Every gradation may be 

 observed from the finest sandstones to the coarse, pebbly varieties 

 known as conglomerate. The size of the grains may vary consider- 

 ably within the limits of a hand specimen, according to the degree 

 the materials have been sorted by water and the action of the wind 

 in bringing in finer particles from the surrounding land. 



While quartz is the principal component which goes to make up 

 sandstones, yet grains of one or more other minerals may be present 

 in greater or less abundance. The more common accompaniments 

 include feldspar, mica, calcite, marcasite, pyrite, magnetite, glau- 

 conite and zircon. A variety of sandstone known as arkose has 

 approximately the same composition as granite, from which it has 

 been derived by disintegration and later consolidation of the mate- 

 rials. If in a sandstone any of the above minerals predominate, so 



