  In this study the crystal structure of hornblende gneiss has been analyzed by
X-ray powder diffraction technique. From X-ray data shows the hornblende is a
mixture of four molecules; quartz (SiO_2 ), albite(Al_1 Na_1 O_8 Si_3 ),
microcline(Al_1 K_1 O_8 Si_3 ), and biotite (H_1.47 Al_1.92 F_1.98 Fe_2.59 K_2
Mg_3.15 Mn_0.09 O_21.47 Si_5.98 Ti_0.27 ),Then determined unit cell parameters,
space group, and the atomic positional coordinates for all consist of the
sample.
