phillipsite: a group of white or reddish crystalline minerals of the zeolite family consisting of a hydrous silicate of calcium and potassium and aluminum
zeolite: any of a family of glassy minerals analogous to feldspar containing hydrated aluminum silicates of calcium or sodium or potassium; formed in cavities in lava flows and in plutonic rocks
equal temperament: the division of the scale based on an octave that is divided into twelve exactly equal semitones