Lizardite in serpentine rock
Asbestos veins in serpentinite
Sample of feldspar
Axinite
Gneiss with garnet
Chrysocolla mineral
Sample of muscovite
Beryl crystals
Zircon crystals on host rock
Citrine
Enstatite
Gneiss with garnet, light micrograph
Concentric banding in agate
Emerald
Kyanite
Microcline mineral
Chromite and serpentine
Neptunite
Magnesite vein in igneous rock
Cut Diopside gemstone
Rose Quartz
Biotite mineral in orthopyroxene
Feldspar and quartz
Almandine
calcite veining in limestone
Quartz coated with silica
Pallasite meteorite fragment
Lapis lazuli, SEM
Moss agate
Pyroxene crystal, thin section
Quartz crystals, SEM
Quartz crystal, SEM
Ruby in zoisite
Chalcanthite crystals in rock groundmass
Linarite in rock groundmass, close-up
Malachite and chrysocolla minerals
Smoky quartz
Fire Opal
Tourmaline on quartz
Rare bright green Uvarovite Garnet
Apophyllite on calcite
Zinnwaldite mineral group
Barytocalcite crystals in rock groundmass
Artinite crystals in rock groundmass
Tourmaline unworked stones
Yellow-green Tourmaline rough
Round cut red Andesine
Cut Quartz gemstone
Stilbite crystal group
Prehnite and okenite
Pink beryl crystal, SEM
Agate
Chalcedony
Hornblende crystals
Brazilianite crystals in calcite
Calcite in mudstone
Ankerite crystals in groundmass, close-up
Smoky quartz crystals
Aragonite crystals
Serpentine groundmass with chrysotile
Tourmaline
Scapolite crystals in rock groundmass
Cut Kyanite gemstone
Cut Pyrope gemstone
Cut yellow Vesuvianite gemstone
Magnesite crystals in groundmass
Trillion cut tourmaline gemstone
Cut green Paraiba Tourmaline gemstone
Cut Zircon gemstone
Graphite on calcite crystals
Serpentine rock, polarised microscopy
Twinned augite crystals
Gibbsite
Zincite in fraklinite
Serpentine Marble specimen
Tourmaline crystal, thin section
Black tourmaline, SEM
Selenite crystals
Fluorite and barite crystals
Cut and polished septarian nodule
Uncut emeralds
Niobite in host rock
Actinolite crystals
Aventurine
Cut Watermelon Tourmaline gemstone
Rough pinkish-red Rubellite
Gypsum crystals
Polyhalite, close-up
Aragonite crystals with sulphur
Sample of limestone
Aragonite-covered crayfish
Cut Indicolite gemstone
Cut Spessartine gemstone
Sample of serpentine
Antigorite, Thurman, New York, USA
Barite crystals
Fluorite crystals
Barite and chalcopyrite crystals
Calcite crystals
Coral calcite crystals
Magnetite and calcite
Flos-ferri aragonite
Pseudomorphic crystal growth
Pink calcite crystals
Zinc ore under ultraviolet light
Zinc ore
Calcite
Septarian nodule
Lithographic limestone
Limestone
Yellow limestone
Calcium carbonate precipitation
Aragonite
Cerussite
Smithsonite encrustation
Botryoidal Malachite on chrysocolia
Fibrous malachite
Sample of chalk
Gypsum stone
Conichalcite and adamite
Apophyllite crystals
Cut pink topaz gemstone
Kaolinite in rock groundmass
Chamosite in rock groundmass
Microcline in rock groundmass
Helvite crystals in rock groundmass
Clinochlore crystals in rock groundmass
Aegirine crystal in rock groundmass
Cordierite crystals in rock groundmass
Short, prismatic phosgenite crystals in rock groundmass
Jamesonite in rock groundmass, close-up
Scapolite mineral sample
Raw garnet crystal
Blue smithsonite in groundmass
Silver crystals in calcite
Botryoidal chalcedony, close-up
Yellow crystal
Brazilianite crystals
Coral sand sample, SEM
Basalt, light micrograph
Wavellite
Meyerhofferite
Rhombohedral siderite crystals
Carnelian
Microlite crystals in groundmass