meionite
/ˈmʌɪənʌɪt/(also mionite) Mineralogy
noun
A tetragonal aluminosilicate mineral that is the calcium- and carbonate-rich endmember of the scapolite series and occurs as transparent, translucent, or pearly crystals of various colours.
Origin
Early 19th century; earliest use found in Journal of Natural Philosophy, Chemistry and the Arts. From French meïonite from ancient Greek μείων lesser, less + French -ite.