QUARRY MATERIALS OF NEW YORK 165 



principal iron mineral is biotite, which forms rather large crystals 

 but is very unequally distributed. There is some secondary chlorite. 

 Black tourmaline, garnet and iron sulphides occur sparingly. The 

 character of the pegmatite thus agrees very closely with the Crown 

 Point occurrence and is no doubt connected with the same series of 

 granite intrusions. 



The product of the quarry is reduced in a mill neai-by, equipped 

 with jaw crusher and rolls and screens for sizing. The material 

 too fine for roofing is sold for concrete and grout. No pottery 

 grades are obtained. The output is hauled by wagons to Ticon- 

 deroga for shipment. 



Mount Defiance quarry 



An abandoned quarry is found on the north end of Mount De- 

 fiance between Montcalm Landing and Ticonderoga. It was worked 

 several years ago by the Ticonderoga Feldspar Co. The rock 

 strictly is not a granite pegmatite, but a coarse phase of the country 

 gneiss which belongs to the syenitic class. It contains hornblende 

 and pyroxene with some quartz and a perthitic feldspar. 



FORT ANN, WASHINGTON COUNTY 



Ashley quarry 



An exposure of pegmatite near Fort Ann has been worked at 

 different times for feldspar and quartz. It is one of the localities 

 from which quartz was obtained for grinding at the mill that was 

 operated at Fort Ann about twenty-five or thirty years ago. More 

 recently it has been a source of feldspar and has been worked inter- 

 mittently according to the prevailing market demand, the last time 

 by Dominick Ashley of Glens Falls. 



The outcrop lies about 2^ miles northwest from Fort Ann at 

 the base of the gneiss ridge, of which the higher part is known as 

 Putnam mountain. It is on or adjoins the farm of Ira D. Gilmore. 

 It consists of a rather irregular area, suggesting somewhat a lens, 

 with a longer axis nearly at right angles to the trend of the ridge 

 or to the northwest. An open pit about 125 feet long and from 

 30 to 40 feet deep has been made but is now largely filled with 

 water. The lens is broadest near the southeastern end where it 

 measures fully 75 feet across. To the northeast it gradually dimin- 

 ishes and wedges out in the gneiss 50 feet beyond the end of the 

 pit. The gneiss wall rock is a laminated biotite variety that may 

 be classed with the Grenville series. 



