926 NEW YORK STATE MUSEUM 



The emery is composed of corundum, magnetite, spinel and garnet 

 in varying proportions. The product is ground and made into 

 wheels, for which purpose it is said to give good satisfaction, though 

 inferior to imported emery. 



The production of emery in 1904 amounted to 1148 short tons, 

 valued at $17,220, which was less than in the previous year. There 

 were four concerns engaged in active mining: the Blue Corundum 

 Co. of Boston Mass., the Tanite Co. of Stroudsburg Pa., H. M. Quinn 

 of ^Philadelphia Pa., and J. R. Lancaster of Peekskill. The Hamp- 

 den Corundum Wheel Co. of Springfield Mass., made no output 

 last"^year. 



FELDSPAR AND QUARTZ 



Feldspar suitable for pottery purposes is obtained near Bedford, 

 Westchester co. It occurs in the pegmatite dikes intersecting the 

 crystalline rocks of that region and is associated with quartz, mica 

 and tourmalin. In some of the dikes the feldspar forms large 

 masses or crystals, quite free from impurities, while in others it is 

 intergrown with quartz; only the former occurrences, however, 

 have commercial value. The feldspar belongs to the variety known 

 as brthoclase, which is characterized by a high potash content. It 

 varies from dark red to white in color. The chemical composition 

 is shown by the following analysis: SiO^, 65.85%; AW 3, 19.32%; 

 FeA, .24%; K2O and Na,0, 14.1%; CaO, .56%; MgO, .08%. 

 The Bedford quarries have been worked since 1878. At present 

 the only producer is P. H. Kinkel & Son. The output is shipped 

 mostly to pottery manufacturers at Trenton N. J. A feldspar 

 quarry opened near Ticonderoga in 1900 was active for a time. 

 The deposit is said to range from 10 to 40 feet in width and to carry 

 75% feldspar, 20% quartz and 5 % mica. 



Vein quartz is produced near Bedford for pottery use and the 

 manufacture of wood filler and silicate paint. Its occurrence is 

 similar to that of the feldspar already described. The largest 

 producer is the Bridgeport Wood Finishing Co. of New Milford Ct. 



GARNET 



The production of garnet for abrasive uses is a well established 

 industry in the Adirondack region. The excellence of the product 

 from a commercial standpoint and the relatively large yield ob- 

 tained from the rocks of this section combine to give the quarries a 

 material advantage over other localities where garnet has-been 

 worked. _ 



