Fornacite is a rare mineral that is often found in hydrothermal deposits. It is also known as calcium hexahydroaluminate and has a chemical formula of CaAl6O10. Fornacite is a relatively obscure mineral, so there are not many synonyms for it. However, some other terms that may be used to describe this mineral include hexahydroaluminate, calcium aluminate, and Ca-Al-O. Fornacite is known for its interesting crystal formations, which often take the form of slender, needle-like structures. It is used in the production of refractory materials, as well as in the manufacture of ceramic glazes and metal alloys.