Most Kryptonian crystals come in the form of a diamond-shaped stick, and are about the length of a hand but other crystals have appeared in different shapes. Most Kryptonian crystals come in the form of a natural clear color but other forms of crystal are known for different purposes. Kryptonian crytals can only be activated, damaged or destroyed by a Kryptonian. This can be argued because Tess Mercer claimed to have destroyed the black crystal in Beast. Although, Tess destroyed the crystal under the command and tutelage of the voice from the Orb. That voice could've instructed her on how to destroy the crystal.