Månadens sten i oktober är Opal.

Opal är en av ädelstensvärldens mest uppskattade ädelstenar. Delas in i 3 undergrupper; Ädelopal, Eldopal och Vanlig opal. Definitionsmässigt är Opaler en undergrupp till kvartser men har amorf kristall struktur. 

Varianter/Sorter

Läs/lär mer om Opal, klicka länkningar nedan för respektive sort (OBS! Endast engelska och kom ihåg att klicka på bakåt knapp i din webbläsare när du vill tillbaks).

Common Opal – Opaque variety of Opal, shows no play of colour.

• Andean Opal – A greenish-blue variety of opal found in Peru.
• Agate Opal – Opal showing concentric banding as in agate.
• Girasol – Bluish-white translucent Opal with reddish reflections.
• Honey Opal – An orange-brown Common opal.
• Hyalite – Colourless, water-clear opal with a strong sheen.
• Hydrophane – A milky variety of Opal that turns translucent or transparent when immersed in water.
• Jasper Opal – A brecciated Jasper cemented by opal.
• Milk Opal – A white Common opal.
• Moss Opal – Milky opal containing dendritic inclusions
• Pink OpalPrase Opal – A green variety of Common opal.
• Semiopal – Historic name for an opal without opalescence
• Wax Opal – A yellow-to brown Opal with a waxy lustre.
• Wood Opal – Petrified wood replaced with Opal.

Fire Opal – A red to yellow variety of Opal.

Precious Opal – A variety of Opal that displays play-of-colour.

• Black Opal – The variety of Precious Opal with a dark background colour.
• Boulder Opal – A variety of Precious Opal found in Queensland, Australia.
• Crystal Opal – Transparent to translucent Precious Opal where colour play is visible both on the surface and in the interior.
• Harlequin Opal – Transparent to translucent Precious Opal with effective mosaic-like colour patterns.
• Matrix Opal – A rock consisting of a (usually) silicified matrix containing veins or blebs of Precious opal.
• Water Opal – A transparent Precious opal with a gelatinous appearance and a bluish sheen.
• White Opal – Precious Opal with a white background.