A multi-pointed star-shaped crystal seen in the third season of Bishoujo Senshi Sailor Moon. They are physical representations of a human's heart, and if forcefully removed and not returned to its owner, the person will eventually die. The Space Sword and Deep Aqua Mirror are hidden within the Pure Heart Crystals of two unknown owners, whom Sailor Uranus and Sailor Neptune are trying to find before the Death Busters can.
Sailor Saturn's initial brooch resembles a Pure Heart Crystal, but is not hers in itself.
