LiAlSiO4

Lithium aluminum silicate, with the chemical formula LiAlSiO4, is a mineral also known by its mineralogical name, eucryptite. It is a ternary compound formed from lithium, aluminum, silicon, and oxygen. Eucryptite typically crystallizes in the hexagonal crystal system. Pure eucryptite is colorless and transparent, but impurities can lead to various colors, often white or pinkish. It possesses a vitreous luster and a Mohs hardness of around 6.5, making it relatively hard.

Eucryptite is found in lithium-rich pegmatites and some metamorphic rocks. It is often associated with other lithium-bearing minerals such as spodumene and lepidolite, as well as quartz and feldspars. While not as common as some other silicates, it is an important indicator mineral for the presence of lithium deposits.

The primary interest in LiAlSiO4 stems from its potential as a source of lithium and as a component in certain ceramic applications. Its thermal expansion properties can be manipulated, making it useful in materials that require resistance to thermal shock. Research has explored its use in glass-ceramics and as a constituent in refractory materials. The extraction and processing of lithium from eucryptite can be complex, presenting challenges for industrial applications compared to more abundant lithium minerals.