The performer shows a large Die (about 4" square), resting on a silk.  The Die is covered with a five sided cover, just big enough to take the Die. The performer picks up the silk and the Die magically penetrates through the middle of the silk.  However, it leaves it's spots behind.  The silk is shaken, and the spots fall out.  The cover is shown and is completely empty.  The Die is shown all around, and it is a solid Die.