Gilson Opal (Cabochon) crystal structure
amorphous synthetic

Gilson Opal (Cabochon)

SiO2*nH2O

Quick Facts

Hardness
5.5
Specific Gravity
2.05
Refractive Index
1.44

Crystal Structure

amorphous

Physical Properties

Crystal Systemamorphous
Hardness (Mohs)5.5
Specific Gravity2.05
CleavageNone
FractureConchoidal
LustreVitreous to resinous

Optical Properties

Refractive Index1.44

Origin & Identification

Originsynthetic
Growth Methodgilson

Interactive Preview

Open this crystal in the CDL Playground to rotate, export, and explore in 3D.

Open in Playground

Natural Counterpart

The natural gem this synthetic imitates

Opal
Opal natural
SiO2.nH2O

Related Minerals

Other minerals in the amorphous system

Glass (Paste) (Faceted)
Glass (Paste) (Faceted)
SiO2 + various metal oxides (lead, barium)
Opal
Opal
SiO2.nH2O
Opal Doublet (Cabochon)
Opal Doublet (Cabochon)
SiO2*nH2O on dark backing
Opal Triplet (Cabochon)
Opal Triplet (Cabochon)
SiO2*nH2O between dome cap and dark backing
View all amorphous minerals →

Learn More

FundamentalsCrystal SystemsFundamentalsOptical PropertiesFundamentalsPhysical Properties