Don't worry, be happy.
Worry stones (palm stones, thumb stones) are smooth, polished gemstones, usually in the shape of an oval with a thumb-sized indentation, used for relaxation or anxiety relief. They are used by holding the stone between the index finger and thumb and gently moving one's thumb back and forth across the stone. Each color/cut of stone, are known to hold their own unique properties. Stones are approximately 1.25" to 1.50" in size, perfect for the pocket!