Colour zoning in ruby from Mong-Shu, Burma

Inclusions of fossil plant debris in opal from Wollo, Ethiopia

Fire opal, Mexico

Dumortierite in rock crystal, Brazil, polarised light

Partially etched diamond crystal

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

Agate from Reichweiler, Germany

Inclusions of hematite in feldspar (sunstone), India

Bubbles and swirls in moldavite (natural glass)