The chin and lower jaw constitute Jigak (Earth Palace), which represents old age asset security, home stability, and supportive relationships. Fleshy, rounded, and broad chins hold wealth securely and indicate high empathy, drawing in loyal juniors. Conversely, extremely sharp (V-line) chins or weak chins suggest potential instability in late life. AI parameters map jaw symmetry and volume index, encouraging proper posture and regular jaw exercises to foster a bright, trustworthy aura.