What is a worry stone, and how does it differ from a palm stone?

Worry stones, with their convenient, portable size and soothingly smooth feel, are a proven method for reducing stress and anxiety. They will help calm your heart, and center your mind. They are most effectively used by holding the stone between your index finger and thumb and gently rubbing your thumb back and forth across the stone in the indentation that has been carved out for you. A palm stone is a stone of approximately the same size, but without the indentation.