Kyanite
Ruby in zoisite
Almandine
Zinnwaldite mineral group
Prehnite and okenite
Quartz crystals, SEM
Feldspar and quartz
Chrysocolla mineral
Stilbite crystal group
Scolecite
Pink beryl crystal, SEM
Wavellite
Microcline mineral
Malachite and chrysocolla minerals
Concentric banding in agate
Zircon crystals on host rock
Axinite
Beryl crystals
Quartz crystal, SEM
Citrine
Quartz coated with silica
Tourmaline
Tourmaline on quartz
Rough pinkish-red Rubellite
Rare bright green Uvarovite Garnet
Almandine close
Raw garnet crystal
Twinned augite crystals
Hornblende crystals
Pallasite meteorite fragment
Sample of muscovite
Tourmaline unworked stones
Cut Kyanite gemstone
Mesolite
Chabazite
Lapis lazuli crystals I
Lapis lazuli crystals II
Smithsonite
Rose Quartz
Tourmaline crystal, thin section
Pyroxene crystal, thin section
Smoky quartz
Apophyllite crystals
Agate
Chalcedony
Diaspore
Sample of feldspar
Lizardite in serpentine rock
Blue labradorite
Citrine crystal group
Moss agate
Emerald
Chalcanthite crystals in rock groundmass
Copper sulphate crystal
Tourmaline cross section
Smoky quartz crystals
Rough topaz
Crocoite
Apophyllite on calcite
Neptunite
Brochantite
Gneiss with garnet, light micrograph
Septarian nodule
Calcium carbonate precipitation
Fluorite mineral
Ankerite crystals in groundmass, close-up
Daisy Gypsum
Magnesite crystals in groundmass
Artinite crystals in rock groundmass
Anatase mineral (titanium oxide)
Rhombohedral siderite crystals
Nitratine mineral (sodium nitrate)
Amethyst crystals
Rhodonite
Labradorite
Chalcocite crystals
Magnetite and calcite
Enargite mineral
Stephanite crystals, close-up
Polybasite crystals, close-up
Hydrated copper sulphate crystals, SEM
Kyanite mineral
Lapis lazuli, SEM
Asbestos veins in serpentinite
Gneiss with garnet
Epidote crystals
Cut Diopside gemstone
Cut Indicolite gemstone
Cut Pyrope gemstone
Cut Watermelon Tourmaline gemstone
Cut yellow Vesuvianite gemstone
Yellow-green Tourmaline rough
Trillion cut tourmaline gemstone
Round cut red Andesine
Cut green Paraiba Tourmaline gemstone
Cut Quartz gemstone
Cut Zircon gemstone
Purple-blue geode
Cyanotrichite crystals on rock surface
Cut Scapolite round gemstone
Rutilated quartz
Blue smithsonite in groundmass
Ruby
Sapphire crystal
Boleite crystals in gypsum groundmass
Variscite, an aluminium phosphate
Cut pink topaz gemstone
Red calcite crystals
Enstatite
Yellow crystal
Black tourmaline, SEM
Kyanite and Staurolite crystals
Fluorapatite crystal, SEM
Sphalerite crystals
Hydrated copper sulphate crystals
Calcite crystals
Coral calcite crystals
Silver crystals in calcite
Brazilianite crystals in calcite
Aragonite crystals
Aragonite crystals with sulphur
Flos-ferri aragonite
Pseudomorphic crystal growth
Calcite crystal
Calcite
Gypsum stone
Graphite on calcite crystals
Cut and polished septarian nodule
Pink calcite crystals
Zincite in fraklinite
Quartz encrusted calcite crystals
Aragonite
Scalenohedral calcite crystals
Calcite crystal rosettes
Meyerhofferite
Cerussite
Barytocalcite crystals in rock groundmass
Scalenohedral calcite, close-up
Stibnite
Glauberite, close-up
Linarite in rock groundmass, close-up
Aurichalcite in limonite groundmass
Native gold on quartz
A piece of Thenardite