Jumping Gems is a progressive routhine with lots of twists and turns. In this effect, both rods appear to have no gems. One diamond gem appears, now it's on both sides of the rod. The diamond jumps to the other rod. Now it's on both sides of that rod. Next there's a diamond on each end of the rod. Then one diamond is pushed up to join the other diamond. Now we lose a diamond, or did it jump to the other rod? Last, it's obvious to the spectator that the lone diamond is under your thumb. Lift your thumb, surprise, it's a ruby!
Easy to do.
Classic in magic.