Show 2 blue silks (45 by 45 cm) and tie them together. Now place them - still in full view of the audience - to one side for a moment. Take a beautiful 'Rainbow Silk', and make it vanish in front of your audience's very eyes. The 'Rainbow Silk' reappears almost instantaneously, now tied between the two blue silks. Get a spectator to untie the silks.
A classic effect which, partly due to the beautiful 'Rainbow silks', is very attractive.