Clinoptilolite Clinoptilolite is a natural zeolite comprising a microporous arrangement of silica and alumina tetrahedra. It has the complex formula: (Na,K,Ca)2-3Al3(Al,Si)2Si13O36·12H2O. Wikipedia https://en.wikipedia.org/wiki/Clinoptilolite Added to support Critical Zone Observatory (CZO) data use cases. ODM2 Variable Name Controlled Vocabulary ODM2 Working Group A vocabulary for describing the name of Variables.