Opal

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Opal – Overview

Intro

Opal is celebrated for play-of-colour and for the wide variety of looks available across white, black, crystal, and boulder material.

Overview

This starter entry positions opal as a phenomenon gem where pattern, brightness, body tone, and stability are central to the buying conversation.

About

This starter entry positions opal as a phenomenon gem where pattern, brightness, body tone, and stability are central to the buying conversation. Opal is presented here as a structured gemstone record ready for linked buyer guides, research posts, and media galleries.

Key Properties

Mineral / materialOpal
ChemistrySiO2·nH2O
Crystal systemAmorphous
ColourWhite, black, crystal and many play-of-colour varieties
Refractive index1.37 – 1.52
Specific gravity1.98 – 2.25
Mohs hardness5.5 – 6.5
LusterVitreous to waxy
TransparencyTransparent to opaque
ToughnessFair