New York State Museum 



RECENT DEVELOPMEiXTS IN THE GYPSUM INDUSTRY IN 

 NEW YORK STATE 



BY ARTHUR L. PARSONS 



Gypsum deposits of rayetteville 



The quarries at Fayetteville are located abaut 2 miles south- 

 west of the village and are situated on two knolls. 



Five companies have quarries here: the National wall plaster 

 CO. and the Adamant wall plaster co. of Syracuse, Mr F. M. Sever- 

 ance, Mr 0. A. Snooks and Mr O. Snooke of Fayetteville. The 

 latter two have small quarries. 



The oldest quarry is that of Mr Severance, which has been 

 worked more than 60 years. The bed of gypsum in this quarry 

 is about 60 feet thick and consists of eight layers varying in thick- 

 ness from 18 inches to 30 feet. It is covered with about 40 feet 

 of shaly rock, together with hydraulic limestone. 



The plaster rock varies in color from light drab in the cap to a 

 dark brown (iron layer), all forms becoming lighter on exposure 

 to air. The so-called ^' slate " consists of fibrous, scaly, and other 

 forms of gypsum; the remaining beds consist almost entirely of 

 compact gypsum. 



The specific gravity varies from 2.68 in the 9 foot layer to 2.33 in 

 the slaty layer. 



The composition is nearly uniform, consisting of calcium sul- 

 fate, 80^ to 90^; calcium carbonate, a trace; magnesium carbon- 

 ate, 5^ or less; alumina, 10^ or less. The amount of carbonates 

 is greatest in the iron layer, showing effervescence in the mass. 

 It is nearly as abundant in the cap layer; it is least in the 

 crystalline layer (the so-called '' slate "). In none of the layers 

 is the quantity sufficient to prove detrimental. To quarry this 

 gypsum, the slate rock above must be stripped. This stripping 

 is accomplished after a portion of the quarry has been worked 

 out, by blasting out a layer of marlite about 4 feet in thick- 

 ness immediately above the plaster 'rock. When sufficient has 

 been blasted, the overlying " slate " falls down into the hole 

 from which the gypsum has been removed, and the new part 

 exposed can be quarried without removing very much of the 



