A shard is the object that Jen,
the last Gelfling, is destined to seek out and return to
The Dark Crystal from which it was broken off years and years ago. This shard's insertion back into the crystal at the precise time when the three suns align is intrical to restoring the balance between good and evil back into the world in which Jen lives.
When Jen has found three probable crystal shards at Auhgra's disheveled house of treasures, he is at first unable to attain which is the true Shard. He plays on his wooden piped instrument a haunting tune of enchantment taught him by the gentle Mystics by whom he was raised. In response to Jen's tune, the true Shard from
The Dark Crystal glows with a eerily purplish tint, revealing itself to Jen as
The One.