Chalcedony
Agate
Fire agate
Carnelian gemstone
Concentric banding in agate
Carnelian
Moss agate
Botswana agate stone
Aragonite crystals
Garnet crystal and rock
Jasper polished stone
Brecciated Jasper stone
Spotted Jasper stone
Yellow Jasper
Kyanite crystal
Labradorite rock crystals
Iron oxide precipitation in agate
Cut and polished agate
Calcite crystal
Calcite
Quartz crystals, SEM
Quartz coated with silica
Amethyst and chalcedony
Citrine
Smoky quartz crystals
Amethyst crystals
Rutilated quartz
Quartz encrusted calcite crystals
Yellow crystal
Agate mineral rock cross section
Jasp agate stone
Jasp agate polished surface
Cabuchon gemstones of jasper
Egyptian jasper stone
Beryl crystals
Pallasite meteorite fragment
Dendrites in agate
Citrine crystal group
Quartz crystal, SEM
Desert rose mineral clusters
Mineral precipitation in agate
Dendritic mineralisations in chalcedony
Pink beryl crystal, SEM
Tourmaline unworked stones
Almandine
Tourmaline on quartz
Prehnite and okenite
Dendritic precipitation in an agate
Carnelian pebble
Botswana agate stones
Round agate geode
Round agate thunderegg
Two agate thundereggs
Turritella agate
Agate slice
Blue lace agate
Dyed agate slice
Moss Agate stone
Amethyst geode
Amethyst geodes
Amethyst stone
Banded Amethyst stone
Amethyst
Beryl stone
Chalcopyrite
Chiastolite stone
Fuchsite mineral stone
Garnet gemstone
Leopardskin jasper stone
Amethyst filled geode
Agate geode
Agate. polarised light micrograph
Carnelia
Axinite
Chrysocolla mineral
Zircon crystals on host rock
Dendritic crystals in chalcedony
Smoky quartz
Aventurine
Tourmaline
Rough pinkish-red Rubellite
Rare bright green Uvarovite Garnet
Gypsum stone
Emerald
Raw garnet crystal
Tourmaline crystal, thin section
Cut agate
Mineral precipitate in agate
Ruby in zoisite
Feldspar and quartz
Polished carnelian stone
Sample of feldspar
Fortification agate
Native gold
Crystals of haematite in quartz
Pseudomorphic crystal growth
Galenite and quartz crystals
Colourful crystals
Tellurium in quartz
Hessite in quartz
Emerald crystal in quartz
Chabazite crystals in quartz
Native gold on quartz
Emerald in quartz
Silica rock crystal samples
Hyacinth quartz
Orthoclase and quartz crystals
Tourmaline cross section
Carnelian.
Pyrolusite in quartz
Zinnwaldite mineral group
Sylvanite crystals
Lapis lazuli, SEM
Gneiss with garnet, light micrograph
Gneiss with garnet
Botryoidal chalcedony, close-up
Rose Quartz
Apophyllite on calcite
Fire Opal
Sample of muscovite
Fayalite
Basalt, light micrograph
Asbestos sample
Cut agates
Geode interior
Rhyolitic geode
Geode interior section
Geode in thin section
Slice of agate
Agate Bridge at Petrified Forest, Arizona
Iron dendrites in agate
Copper