The mended Pure Crystal.
The Dark Crystal turning into the Pure Crystal again.
The UrSkeks' return in front of the Pure Crystal.
Also known as the Crystal of Truth, it was the original form of the Dark Crystal, housed within the Castle of the Crystal's Crystal Chamber.
It was split by a Skeksis 1,000 years before the events of the movie and became the Dark Crystal, but 1,000 years later Jen reunited the Crystal Shard with the rest of the crystal, turning it back into the Pure Crystal.
Production photo of Mystics and Skeksis in front of the Pure Crystal.