Pendulums are divination tools, used to answer yes/no questions to assist in providing direction.  They work by responding to your subconscious mind.
 
Tiger's Eye
Associated with Solar Plexus
This stone is known for helping one to feel protected and to boost self-confidence.  It aids in helping to combat feelings of jealousy and to feel grounded while pursuing your dreams.
 
This listing is for 1 pendulum intuitively chosen by me.