The magician tells the audience he got a magic diamond necklace that has prediction power.
Nothing special with that necklace.
He shows 5 cards with five-pointed star on each side
and turns his back.
He asks audience to choose one card from the 5 and turn it over.
When he turns back again, he hangs the necklace over each card.
The necklace shakes itself when it goes to the selected card.
An insteresting and powerful prediction trick.
Easy to learn.