Name:  Dolomitic limestone

Geologic Name:  Lockport Dolomite

Reference:  Alling, H.L., Quantitative petrology of the Genesee
gorge sediments: Proc. Rochester Acad. Sci., v. 9, no. 1, 
p. 53-55, 1946.

Microscopic characters:  The rock contains an aggregate of rhombs and
angular grains of dolomite with abundant grains of quartz.  There is
some carbonaceous and argillaceous material present and occasionally
pyrite is noted.