lithomancy

/ˈlɪθəˌmænsi/
noun
  1. Divination or fortune-telling by interpreting the appearance, arrangement, or movement of stones or gems.
    • The museum exhibit explained how lithomancy was used by certain tribes to predict weather and harvests.
    • In ancient times, some cultures practiced lithomancy by casting stones and reading their patterns.
    • She studied lithomancy as a hobby, learning to interpret the colors and shapes of different crystals.