Delicate araganite structures in cave
Araganite crystals in limestone cave
Aragonite crystals
Former limestone cave now exposed to sea
Aragonite
Cave exploration, Brazil
Cave stalagmites
Grotta del Fico, Sardinia, Italy
Strontianite crystals
Krizna Jama Cave, Loz Valley, Slovenia
Flos ferri aragonite in rock groundmass
Limestone cave
Grotta Su Marmuri, Sardinia, Italy
Pisolitic calcium carbonate
Aragonite crystals, Morocco
Pamukkale travertine deposits
Aragonite botryoidal precipitate
Aragonite specimen
Aragonite crystals with sulphur
Flos-ferri aragonite
Pisolite
Calcium carbonate precipitation
Cerussite
Aragonite-covered crayfish
Aragonite (Sprudelstein)
Old Cave houses in Guadix
Old Cave houses in Guadix, Spain
Pseudohexagonal aragonite crystals
Mineral samples
Stalactites, Toirano caves, Liguria, Italy
Stalagmites, Toirano caves, Liguria, Italy
Caves of Arta, Mallorca, Spain
Geothermal limestone terrace
Geothermal limestone deposit
Aragonite floral crystals
Stalactites and stalagmites, Liguria
Mineral deposits on rocks in a cave, Thailand
Quartz stalactites
Iridescent ammonite fossil
Ammonite fossils
South Africa, Western Cape, Oudtshoorn, Cango Cave 1
Synthetic abalone shell, SEM
Caves in a sea cliff on Sardinia, Italy
Underwater limestone cave formations
Sandstone cliffs, Corfu, Greece
Cave curtain formation
Selenite crystals on a dried lake bed
Brandwag buttress, South Africa
Cave of Swords, Naica Mine, Mexico
Barenloch, karst cave in Jura mountains, Switzerland
Boudinage in dyke crossing serpentinite
Rock formations, Karnataka, India
Malachite and adamite
Cave
Flute marks on mudstone
Volcanic solfatara formation
Montenegro, Cetinje, Lipa Cave
Man exploring Krizna Jama Cave, Loz Valley, Slovenia
Stalactites in a cenote
Carlsbad Caverns National Park, New Mexico, USA
Glacial pothole
Eisenblute
Volcanic rock cavities
Avakas Gorge, Cyprus
Sea stack, Wales
Orange lichen on glacier polished rock
Folded schists
Igneous rocks near Arbatax, Sardinia, Italy
Limestone pavement
Beinn Alligin, Scotland
Carboniferous limestone pavement, Malham Cove
Red sandstone cliffs, Wales, UK
Colourful rock strata, UK
Chalk cliffs, Cyprus
Baredine cave, Croatia
Stalactites in cave
Croatia, Island of Krk, Dobrinj, View of Biserujka cave
Penghu Blue Cave; Xijiyu;Penghu;Taiwan
Rock formations on a cave roof
Whale Cave;Xiaomenyu;Penghu;Taiwan
Granite on Capo Testa, Sardinia, Italy
Italian medieval city on volcanic neck
Spain, Andalusia, Nerja, Cuevas de Nerja, stalactites
Botryoidal aragonite
Agglestone Rock, UK
Stalactites and stalagmites in cave
Eroded sandstone
Rock concretions
Sedimentary rock outcrop
Basalt outcrop
Ute Mountain Reservation, USA
Chandelier Cave, Palau
Quartz mineral in limestone rock
The Sulphur Cave, New Zealand
Sulfur crystals, Italy
Pyrite with Hematite, Italy
Sulfur, Sicily, Italy
Sulfur, Italy
Clinochlore with garnets
Diamond miners, South Africa
Travertine terrace waterfall, Croatia
Rhodonite specimen
Selenite crystal from Cave of Crystals
La Tarta volcanic outcrop, Tenerife
Interior of Deer Cave
Entrance to Deer Cave
Limestone pillar on Sardinian coast, Italy
Amber
Giant's Causeway
Folded gneiss
Chrysocolla
Appenzell Alps, Switzerland
Pedestal erratics
Pedestal erratic
Kambhorn reflected in lagoon, Iceland
Skjaldbreidur shield volcano, Iceland
Karst rock formation, Switzerland
Dioptase, Namibia
Dioptase, Kazakhstan
Spinel, Bridgewater, Vermont
Beryl, Massachusetts
Golden Beryl, Nottingham, New Hampshire
Smoky Quartz, Rutilated
Apophyllite and Prehnite
Calcite crystals
Apophyllite crystals
Calcite
Cavansite
Union road agate
Agate
Franklinite
Mollusc shell, SEM
Limestone pavement, New Zealand
Germany, Bavaria, Franconia, Upper Franconia, Franconian Switzerland, Betzenstein, View of Klauskirche cave
Alvados caves, Leiria, Portugal
Sodalite.
Rhodonite.
Polished variscite stone
Banded jasper
Rhodochrosite
Dioptase mineral sample
Cordierite
Weathered granitic bedrock
Eroded and pitted rock
Martian drilling site, Curiosity image
Conical hill
Banding patterns
Granite rock arch in mountains in Namibia
United Kingdom, Scotland, Sutherland, Durness, entrance to Smoo Cave
Sulphur deposits on Mutnovsky volcano crater floor
Colorful danxia