The name given to the monoclinic lithium pyroxene LiAl(SiO₃)₂. Spodumene commonly occurs as white to yellowish prismatic crystals, often with a “woody” appearance, exhibiting the 87° pyroxene (110) cleavages. It is easily identified during heating in a flame by the red color given off, accompanied by a marked swelling of the fragment. Spodumene usually contains an appreciable quantity of hydrogen substituting for lithium. At 720°C (1330°F), spodumene inverts to a tetragonal form, β-spodumene, which is accompanied by a 30% increase in volume. Spodumene is capable of forming immense crystals in nature. A single crystal 47 ft (14.3 m) in length and 5 ft (1.5 m) in diameter, as well as others almost as large, has been found at the Etta mine in South Dakota. This implies the remarkable ability of a single crystal to replace a large variety of preexisiting minerals and yet maintain the integrity of a single crystal, a crystal growth unequaled elsewhere in nature.