«Red fox agate» from Patagonia, Argentina

Midge included in amber from the Baltic coast, polarised light

Inclusions of rock crystal and rutile needles in quartz, Brazil, polarised light

Inclusions of anatase crystal and rutile fibres in rock crystal from Brazil

Spinel crystal in dolomite marble, Burma

Stress fissure («sun spangle») in baltic amber

Inclusions of hematite in aquamarine, Tanzania

Inclusions of gilalite aggregates in rock crystal from Brazil

Inclusions of fossil plant debris in opal from Wollo, Ethiopia