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

Agate from Anzi, Maroc

Inclusions of chrysotile fibres in demantoide garnet from Ural Mountains, Russia

Stress fissure («sun spangle») in baltic amber

Partially etched diamond crystal

Colour zoning in ruby from Mong-Shu, Burma

Dumortierite in rock crystal, Brazil, polarised light

Inclusion of apatite in ruby from Tanzania

Two-Phase inclusions and rutile needles in rock crystal from Brazil