Hyalite
![A sample of hyalite](/Images/godic/202501/19/Hialit,_opal_szklany_Czechy_ok._Podboran1020.jpg")
![Fluorescent hyalite under ultraviolet light](/Images/godic/202501/19/Hyalite_fluorescence1020.jpg")
Hyalite is a form of opal with a glassy and clear appearance which may exhibit an internal play of colors if natural inclusions are present. It is also called Muller's glass, water opal and jalite. The name Müller's glass derived from the name of its discoverer, Franz-Joseph Müller von Reichenstein.