offretite
/ˈɒfrətʌɪt/Mineralogy
noun
A mineral of the zeolite group which is a hydrated aluminosilicate of potassium and calcium and crystallizes in the trigonal system as colourless prisms.
Origin
Late 19th century; earliest use found in Journal of the Chemical Society. From French offrétite from the name of Albert J. J. Offret, French mineralogist + -ite -ite.