Name:  Cherty limestone

Geologic Name:  Onondaga Limestone

Reference:  Sutton, R.G., Stratigraphy and structure of the Batavia
Quadrangle: Rochester Academy of Science Bull., v. 9, no. 5-6, 
p. 348-408, 1951.

Microscopic characters:  The slide consists of an intimate mixture of
calcite and chert.  In patches the carbonate predominates while in 
others the chert predominates.  Sharp rhomba of carbonate occurr
in the more cherty areas.  Small grains and specks of pyrite and
ferrite are abundant.