1) Oxide mineral 
Chlormayenite (after Mayen, Germany), Ca12Al14O32[☐4Cl2], is a rare calcium aluminium oxide mineral of cubic symmetry. It was originally reported from Eifel volcanic complex (Germany) in 1964. It is also found at pyrometamorphic sites such as in the Hatrurim Formation of Israel and in some burned coal dumps. It occurs in thermally altered limest...