Partially etched diamond crystal

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

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

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

Agate from Reichweiler, Germany

Inclusions of gilalite aggregates in rock crystal from Brazil

Twin-crystal of chrysoberyl

Two-phase inclusions in tourmaline from Namibia

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