Two-phase inclusion in amethyst, Brazil

Inclusions of rutile (dark crystal and fine needles) and clusters of zircon grains in umbalite garnet, Tanzania

Agate from Anzi, Maroc

Spinel crystal in dolomite marble, Burma

Inclusions of gilalite aggregates in rock crystal from Brazil

Inclusion of apatite in ruby from Tanzania

Fire opal, Mexico

Bubbles and swirls in moldavite (natural glass)

Natural etching structure on a crystal face of diamond (trigons), polarised light