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NEW YORK STATE MUSEUM 



Production of limestone by counties in 1915 



MARBLE 



Marble, in the commercial sense, like granite, includes a variety 

 of rocks that lend themselves to building or decorative uses. Most 

 commonly, the name signifies a crystalline aggregrate of calcite or 

 dolomite, as distinguished from ordinary limestones which at best 

 are of indistinctly crystalline nature. At the same time it implies 

 the feature of attractiveness by reason of color and the ability to 

 take a lustrous polish. Rocks possessing all these features are 

 marbles in the strict sense to which the name may be applied with- 

 out qualification. Some compact or granular limestones that lack 

 the elements of thorough crystallinity make, however, a handsome 

 appearance when polished, and such are commercially classed as 

 marbles. Fossil marbles, black marbles, and a few other kinds are 

 commonly of the noncrystalline type. Serpentine marble, or verde 

 antique, is made up for the most part of the mineral serpentine, a 

 silicate of magnesium and iron, and is therefore not related to the 

 varieties already described. Ophitic limestone, or ophicalcite, is a 



