Lithology      Rhyolite
Sample#        AP-939-221
Chemistry
SiO2           73.66
Al2O3          14.76
Fe             1.96
CaO            0.10
TiO2           0.12
MnO            0.02
K2O            4.75
MgO            0.84
Na2O           1.37
P2O5           0.02
PPC            2.40
X-Ray Diffraction
               Quartz
               Plagioclase, Potassium Feldspar
               Mica
