Based on MacDonald’s thermodynamic prediction that minerals should so orient that strain energy is maximized, the preferred orientations of calcite, high and low quartz, and ice are calculated for a stress field consisting of a single component. The following planes should be approximately normal to the stress: ice and calcite, the planes {10̄11}; high quartz, the planes {10̄12}; and low quartz the planes {02̄21}. A number of grains at equilibrium will have c-axes which occupy girdles about the single-stress component. The equations for strain energy of hexagonal minerals in a stress field of three different principal stresses are derived and applied to the orientation of ice (—2°C.). The preferred orientation depends upon ratios of principal stresses and upon stress difference and confining pressure independently. The c axes of grains tend to lie on small-circle girdles about the unique principal stress in a uniaxial stress field.