Composition:

Petrographic Description:  A medium- to fine-grained porphyritic rock with 
a felty texture.  Phenocrysts of olivine, some with probable reaction rims, are
set in a groundmass of plagioclase laths, olivine, clinopyroxene (augite?),
opaques, and interstitial glass.

Microprobe Analysis:  None.

Chemical Analysis:  (by John Marinenko, USGS, Reston, VA.)
SiO2  49.52
CaO  10.54
TiO2  3.11
Na2O  2.33
Al2O3  12.91
K2O  0.62
Fe2O3  1.78
H2O  0.19
FeO  9.45
P2O5  0.30
MnO  0.17 
Cr2O3  0.06
MgO  9.07
TOTAL  100.05
