It is also called Muller's glass, water opal, and jalite. Müller's glass is named after its discoverer, Franz-Joseph Müller von Reichenstein.

Hyalite is an amorphous form of silica (SiO₂) formed as a volcanic sublimate in volcanic or pegmatic rock and is thereby considered a mineraloid. It contains 3–8% water, either as a silanol group or in molecular form.

Opalescent hyalite is used in jewellery, and well-formed samples are of interest to collectors due to their unusual appearance, mode of formation and relative rarity.

It is sometimes mistaken for resin opal or silica glass since they both may appear clear and globular, but it can be identified under ultraviolet light due to its bright green fluorescence.

According to Metaphysical Healers Hyalite is meant to put one in a calming state of mind and ease the emotional stress that one may be experiencing physically.

Hyalite Opal can help one see a different perspective of ones day-to-day life, showing one how energy needs to be expanded and contracted depending on ones needs.

Due to Hyalite Opal being a high-vibrational stone, it is recommended pairing this crystal with grounding energies that come from Black Tourmaline, Shungite, Garnet or Petrified Wood.

Hyalite allows old emotional issues (including past life issues) to come to the surface to be acknowledged and cleared. It also does the same with old repeating behavioural patterns.