Samus observes a Phazite-plated door.

Phazite is a more durable form of the highly radioactive substance Phazon found in Metroid Prime 3: Corruption. It is present on all explored planets and spaceships in the game. Its most common form is a type of plating with a blue marbled effect. Phazite is used extensively by the Space Pirates, often to guard key areas, or as a form of armor. With the use of the X-Ray Visor and the Nova Beam, Samus can see through Phazite and fire through it. The plating is normally blue, but in very rare occurence it is red. Red Phazite is prized for its rarity by the Pirates and as such, is reserved for the armor of Pirate Commanders. No single known weapon can pass through Red Phazite.

It is unknown if Red Phazite has any connection to the Red Phazon found in the Impact Crater on Tallon IV. Phazite can only be penetrated with a high-frequency beam, therefore the Nova Beam may fire through the substance.

Several creatures have developed a similar form of plating to Phazite through Phazon mutation, as an armor or exoskeleton. These include the Phazon Metroid, Phazon Hopper, Hopping Metroid, Metroid Hatcher, Omega Ridley (who can generate the substance at will), and the Tentacle in the Pirate Homeworld Seed. All these organisms can be targeted internally by the use of the X-Ray Visor and Nova Beam (excluding the Hopping Metroid and Phazon Hopper).