The Crystal of Fire is a clear stone with the Kryptonian symbol for "P." 
Powers and Abilities
It can restore a Kryptonian's powers and abilities and possibly break a magic spell (Spell).
In 2004, Lex unearthed an ancient statue containing the crystal. Lex possessed the Crystal of Fire for only a few hours until Clark, brainwashed as Kal-El, took the stone from Lex's jet and placed it on an altar in a hidden room inside the Kawatche Caves in Smallville.
Later, Clark's powers were magically stripped by Countess Margaret Isobel Thoreaux, who possessed Lana Lang and embarked on a quest to find the Stones of Power. The stripping process was symbolized by a colorful light, emitted from Clark's chest. When Isobel tried to remove the crystal from the altar, it burned her hand, and when Clark then grabbed the Crystal of Fire, his powers were restored, symbolized by the same light that left the crystal and entered Clark's body. Therefore, it is unclear, whether the crystal somehow broke Isobel's spell - activated by her touch - and transferred the power's back to Clark or if it just temporarily absorbed and housed Clark's powers as long as he could not physically or mentally interface with the crystal to recharge himself.
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