 Its chemical formula is (K,Ba)[Al(Si,Al)Si2O8], and it has a hardness of 6 – .The name "hyalophane" comes from the Greek "hyalos", meaning "glass", and "phanos" meaning "to appear".An occurrence of hyalophane was discovered in 1855 in Lengenbach Quarry, Imfield, Binn valley, municipality of Binn, Canton of Valais, Switzerland.