hyalite
Definition
Noun (mineralogy): A colorless, transparent, glassy variety of opal, often found in botryoidal or globular forms. It is a form of hydrated silica (SiO₂·nH₂O) that lacks the play-of-color typical of precious opal, instead resembling clear glass or ice.
Usage Examples
- (A transparent, glassy opal specimen.)
- (A property of this specific opal variety.)
Advanced Usage
"Hyalite opal": A more precise term used in gemology to distinguish it from other opal varieties.
- The hyalite opal was set in a silver pendant, valued for its water-clear transparency. (A gemstone use of the mineral.)
"Hyalite encrustation": A thin, glassy layer of hyalite that can form on rock surfaces.
- The basalt cliffs were covered with a delicate hyalite encrustation. (A geological formation.)
Variants and Related Words
- Hyaline (adj): Glassy or transparent in appearance.
- The hyaline cartilage has a glassy, translucent quality. (A term used in anatomy and mineralogy.)
- Hyaloid (adj): Resembling glass; transparent.
- The hyaloid membrane in the eye is a clear, glass-like structure. (A biological term.)
Synonyms
- Glass opal: An informal synonym for hyalite.
- Müller's glass: A historical name for hyalite, named after the German mineralogist.
Related Idioms
- "Clear as hyalite": A rare simile meaning perfectly transparent or obvious.
- Her explanation was as clear as hyalite, leaving no room for doubt. (An idiomatic comparison emphasizing clarity.)
Notes on Usage
- Hyalite is not a common gemstone due to its softness (Mohs hardness ~5.5) and tendency to crack, but it is prized by mineral collectors for its unique fluorescence and glassy appearance.
- The word derives from Greek (glass) plus the mineral suffix .