Epigenetic inclusion (probanly melanterite) in quartz, Brazil, crossed polarisers

Bubbles and swirls in moldavite (natural glass)

Dumortierite in rock crystal, Brazil, polarised light

Agate from Reichweiler, Germany

Partially etched diamond crystal

«Red fox agate» from Patagonia, Argentina

Inclusions of fossil plant debris in opal from Wollo, Ethiopia

Inclusions of hematite in aquamarine, Tanzania

Spinel crystal in dolomite marble, Burma