Name:   Hypersthene Gabbro (Norite)

Geologic Name:  Elizabethtown gabbro

Reference:  Kemp, J.F. and Ruedemann, R., Geology of the Elizabethtown
and Port Henry quadrangles: New York State Mus. Bull. 138, p. 52-57, 1910.

Microscopic characters:  Hypautomorphic-granular textrue.  The principal 
constituent is lath-shaped labradorite with dust-like inclusions.  Hypersthene,
granular patches of biotite, hornblende and olivine with magnetite stringers
are the other essential minerals.  There is a small amount of pyrrhotite
and considerable titaniferous magnetite.  Large amounts of garnet appear
as a reaction product in the labradorite.