Skyfire
Skyfire is a type of fiery rock that composes the Orb in the Sky seen in The Brightest Night. When a dragon holds a piece, their minds are shielded from being read by telepathic dragons. For example, Moonwatcher and Darkstalker failed to read Turtle and Onyx's mind. If the rock is in a mind-reading NightWing's talons, then the dragons cannot read any other minds, whether or not the mind they are trying to read is shielded by a piece.
Onyx claimed she found her piece when something fell out of the sky, burning through and killing her mother. Onyx called it skyfire, and kept the piece that killed her mother on an amulet worn around her neck. Turtle found a large piece that crashed into the ocean when he was swimming with some of his brothers. He made a gold armband with some pieces broken off of the rock in it.
Near the end of Moon Rising, Moonwatcher asked Turtle to take some pieces of skyfire off of his bracelet, and she then gave the rocks to Qibli, Winter, and Kinkajou as a gift so that she couldn't read their minds and so they could keep their thoughts private.
In the beginning of Winter Turning and the very end of Moon Rising, Moon told Turtle to 'give Winter one of the rocks'.
