«Red fox agate» from Patagonia, Argentina

Dumortierite in rock crystal, Brazil, polarised light

Dendrites in agate

Colour zoning in ruby from Mong-Shu, Burma

Fluid inclusions containing mica and quartz, in aquamarine from Pakistan

Bubbles and swirls in moldavite (natural glass)

Inclusions of fossil plant debris in opal from Wollo, Ethiopia

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

Fluid inclusions in quartz with bituminous daughter minerals, China