Crystal Pendulum, Mentalist - w/ Cards

The magician tells the audience he got a magic Crystal Pendulum that has prediction power.
He shows 5 cards with star on each side and turns his back.
He asks audience to choose one of the cards and turn it over.
When he turns back again, he hangs the necklace over each card.?
The necklace moves by itself when it goes to the selected card.?
An interesting and powerful prediction trick.
Easy to learn.

Whole product comes with :5 cards printed with a star, one Crystal Pendulum and instructions.