Bubbles and swirls in moldavite (natural glass)

Inclusions of rock crystal and rutile needles in quartz, Brazil, polarised light

Colour zoning in ruby from Mong-Shu, Burma

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

Agate from Reichweiler, Germany

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

Stress fissure («sun spangle») in baltic amber

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

Inclusions of hematite in feldspar (sunstone), India