I once happened to see a stone whose owner called it a magic stone. In reality it was quite ordinary, but it often changed its color; especially when in the hand of a particular person it showed a different color and shade. So a stone can respond to a person's mind, and this teaches that there is a great deal to explore in the mineral kingdom. This is not a discovery of today; it was known to the people of ancient times. We read in the Persian poems of Jelal-ud-Din Rumi that God slept in the mineral, dreamed in the vegetable, became conscious in the animal, and realized Himself in the human being.