- Absolute dating
- Abyssal plain
- Acanthite
- Acanthodians
- Accident
- Accretion
- Acicular
- Acid rock
- Actinium
- Actinolite
- Adamantine
- Aftershock
- Age of Mammals
- Age of Reptiles
- Agglomerate
- Aggregate
- Agnatha
- Ajoite
- Alamosite
- Albian
- Albite
- Alfred Wegener
- Algae
- Alignment
- Alkaline
- Allanite-(Ce)
- Allophane
- Alluvial fan
- Alluvium
- Almandine
- Aluminum
- Alunite
- Amber
- Americium
- Amesite
- Amethyst
- Ammonite
- Amoeba
- Amorphous
- Amphibole
- Amphibolite
- Amygdaloidal
- Analcime
- Anatexis
- Anatomical
- Andalusite
- Andesite
- Andradite
- Anglesite
- Angular
- Angular unconformity
- Anhedral
- Anhydrite
- Ankerite
- Anorthite
- Anoxia
- Antennae
- Antigorite
- Antimony
- Antlerite
- Aperture
- Aphanitic
- Aphantic
- Aplite Granite
- Aplogranite
- Appendages
- Aptian
- Aquifer
- Aragonite
- Aragonite sea
- Arborescent
- Archaea
- Archean
- Archipelago
- Arenaceous
- Arenite
- Arenitic
- Argillaceous
- Argon
- Arkose
- Arkosic sandstone
- Arsenic
- Arthropod
- Arthur Flagg
- Asbestos
- Ash
- Asphalt
- Asscher Cut
- Assembled gem
- Astatine
- Asthenosphere
- Atacamite
- Atomic Mass
- Atomic Number
- Attrition
- Augite
- Aureole
- Aurichalcite
- Austinite
- Autochthon
- Ayers Rock/Uluru
- Azurite
- Bacteria
- Baguette Cut
- Banded iron formation
- Barite
- Barium
- Barnes Conglomerate
- Barremian
- Basalt
- Basement rock
- Basic rock
- Basin
- Basin and Range
- Batholith
- Beach
- Beaverite-(Cu)
- Bed
- Bedding
- Bedding plane
- Bed-load
- Bedrock
- Before Present
- Beidellite
- Bementite
- Benthic
- Berkelium
- Berriasian
- Beryl
- Beryllium
- Beudantite
- Bideauxite
- BIF
- Bioerosion
- Biological weathering
- Bioluminescence
- Biostratigraphy
- Biostratinomy
- Biotite
- Bioturbation
- Bismuth
- Bituminous
- Bivalve
- Bixbyite
- Bladed
- Blueschist
- Bobmeyerite
- Bohrium
- Boleite
- Bony fishes
- Borates
- Bornite
- Boron
- Boron mineral
- Botryoidal
- Boudin
- Boulder
- Boulder clay
- Brachiopod
- Brackish
- Braunite
- Breadcrust bomb
- Breccia
- Brittle
- Brochantite
- Bromargyrite
- Bromine
- Bryozoa
- Buckling
- Burgess Shale
- Burial
- Cabinet specimen
- Cabochon
- Cabochon Cut
- Cadmium
- Caecilian
- Calcareous
- Calcareous duricrust
- Calcareous nannofossils
- Calcareous nannoplankton
- Calcification
- Calcite
- Calcite sea
- Calcium
- Calcium carbonate
- Calcrete
- Caldera
- Caledonite
- Californium
- Cambrian
- Cambrian explosion
- Campanian
- Canyon de Chelly
- Cap carbonates
- Carat Weight
- Carbon
- Carbonaceous
- Carbonate
- Carbonate hardgrounds
- Carbon film
- Carboniferous
- Carleton B. Moore
- Carnotite
- Cartilaginous fishes
- Cassiterite
- Casting
- Celadonite
- Cementation
- Cenomanian
- Cenote
- Cenozoic
- Cephalon
- Cerium
- Cerro de la Silla
- Cerussite
- Cesium
- Chalcanthite
- Chalcocite
- Chalcophanite
- Chalcopyrite
- Chalk
- Chalky
- Chamosite
- Charles Darwin
- Charles Lyell
- Charles Richter
- Chelicerate
- Chemical formula
- Chemical weathering
- Chert
- Chiricahua National Monument
- Chlorargyrite
- Chlorine
- Chlorite
- Chondrodite
- Chromium
- Chronospecies
- Chrysocolla
- Chrysotile
- Cinnabar
- Clast
- Clastic
- Clay
- Clay mineral
- Cleavable
- Cleavage
- Clinoatacamite
- Clinoclase
- Clinozoisite
- Cnidaria
- Coal
- Coal swamp
- Coarse-grained
- Cobalt
- Cobble
- Coccolith
- Coccolithophore
- Coelophysis
- Color
- Colossal Cave
- Columbia
- Columbian Mammoth
- Columnar
- Columnar joints
- Colusite
- Compact
- Compaction
- Compression
- Conchoidal
- Concretion
- Conductor
- Conglomerate
- Coniacian
- Conichalcite
- Connellite
- Contact metamorphism
- Continental crust
- Continental margin
- Continental shelf
- Contraction
- Convergent boundary
- Copal
- Copernicium
- Copiapite
- Copper
- Coprolite
- Coquimbite
- Coral
- Coralloidal
- Cordierite
- Core
- Core stone
- Corkite
- Coronadite
- Corundum
- Country rock
- Covellite
- Cowlesite
- Crater
- Crater-lake Caldera
- Craton
- Creaseyite
- Creep
- Cretaceous
- Cretaceous-Paleogene Extinction
- Crinoid
- Crocoite
- Cross-bedding
- Crude oil
- Crust
- Crustacean
- Crustal
- Cryogenian
- Cryptocrystalline
- Cryptomelane
- Crystal
- Crystal class
- Crystal face
- Crystal form
- Crystal habit
- Crystalline
- Crystallinity
- Crystallization
- Crystallized urine
- Crystallography
- Crystal system
- Cubanite
- Cube
- Cubic
- Cubo-octahedron
- Cuprite
- Curium
- Cushion Cut
- Cyanobacteria
- Cyanotrichite
- Cynodont
- Dacite
- Darmstadtium
- Daughter product
- Dead cave
- Death Valley
- Deccan Traps
- Deformation
- Degradation
- Delafossite
- Delta
- Dendrite
- Dendritic
- Dense
- Denudation
- Deposition
- Descloizite
- Desert
- Detachment fault
- Detrital
- Devilline
- Devonian
- Diaboleite
- Diagenesis
- Diamictite
- Diapir
- Diatomite
- Dickite
- Differential erosion
- Digenite
- Dike
- Dinocyst
- Dinoflagellate
- Diopside
- Dioptase
- Diorite
- Dip slope
- Dipyramidal
- Disconformity
- Disseminated
- Distorted crystal
- Divergent boundary
- Djurleite
- Dodecahedral
- Dodecahedron
- Dolerite
- Dolomite
- Dome
- Dravite
- Drill core
- Dripping Spring Quartzite
- Dropstone
- Drumlin
- Druse
- Dubnium
- Ductile
- Duftite
- Dull
- Dumortierite
- Dunite
- Duricrust
- Dysprosium
- Earthquake
- Earthy
- Echinoderm
- Echinoid
- Eclogite
- Ecological niches
- Ecology
- Ecosystem
- Ediacaran
- Edward Drinker Cope
- Edwin Colbert
- Eemian
- Eemian transgression
- Effervesce
- Effusive eruption
- Einsteinium
- Elastic
- Element
- Emerald Cut
- Enargite
- Eoarchean
- Eocene
- Eon
- Epicenter
- Epidiorite
- Epirogenetic
- Epoch
- Epsomite
- Equant
- Erbium
- Eriochalcite
- Erionite-K
- Erosion
- Erratic
- Eruption
- Escarpment
- Esker
- Estuary
- Eugeosyncline
- Euhedral
- Eukaryotic
- Europium
- Eurypterid
- Eustatic movements
- Evaporation
- Evaporite
- Evolutionary
- Exfoliation
- Exoskeleton
- Expansion
- Explosive eruption
- Extension
- Extinct
- Extinction event
- Extrusive
- Face
- Facies
- Famatinite
- Fanning
- Fault
- Fault zone
- Fauna
- Feldspar
- Fels
- Felsic
- Fermium
- Ferricrete
- Ferrimolybdite
- Ferromagnesian
- Fiber
- Fibrous
- Filiform
- Fine
- Fine-grained
- Fissility
- Fission track dating
- Flandrian
- Flandrian transgression
- Flash flood
- Flerovium
- Flexible
- Floodplain
- Flora
- Flowstone
- Fluorescence
- Fluorine
- Fluorite
- Fold
- Foliated
- Foliation
- Foraminifer
- Form taxon
- Fornacite
- Forsterite
- Fossil
- Fossil
- Fossiliferous
- Fossilization
- Fossilized
- Fossil record
- Fossil Reef
- Fracture
- Fragmental
- Fraipontite
- Francium
- Freeze-thaw
- Freibergite
- Friedrich Mohs
- Fumarole
- Fusakichi Omori
- Ga
- Gabbro
- Gadolinium
- Galena
- Gallium
- Garnet
- Garronite-Ca
- Gaskiers Glaciation
- Gastrolith
- Gem cut
- Gemology
- Gemology
- Gemstone
- Gemstone
- Geochemistry
- Geode
- Geological
- Geological history
- Geologic map
- Geologic time scale
- Geology
- Georgerobinsonite
- Georges Cuvier
- Geosyncline
- Germanium
- Gila Conglomerate
- Glacial erosion
- Glacial erratic
- Glacial plucking
- Glacial polish
- Glacial till
- Glacier
- Glass
- Glassy
- Glauberite
- Glauconite
- Glenn Canyon and Rainbow Bridge
- Globular
- g/mol
- Gneiss
- Goethite
- Gold
- Gondwana
- Gondwanaland
- Gossan
- Graben
- Grain
- Grand Canyon
- Granite
- Granitoid
- Granoblastic
- Granodiorite
- Granular
- Graptolite
- Gravel
- Graywacke
- Greasy
- Great Dying
- Great Oxygenation Event
- Great Rift Valley
- Greenstone
- Greenstone belt
- Grossular
- Groundwater
- Groutite
- Grus
- Gymnosperm
- Gypsum
- Habit
- Hadean
- Hafnium
- Half-life
- Halides
- Halite
- Halloysite-10Å
- Halotrichite
- Hanging valley
- Hardness
- Hardpan
- Hassium
- Hauterivian
- Hawai’ian Volcanoes
- Heart Cut
- Helium
- Hematite
- Hemicrystalline
- Hemihedrite
- Hemimorphite
- Hetaerolite
- Hexagonal
- Hexahydrite
- Hinge
- Hisingerite
- Hollandite
- Holmium
- Holocene
- Holocrystalline
- Hopper-shaped
- Hornblende
- Horn coral
- Hornfels
- Horst
- Hot spring
- Hydrobiotite
- Hydrocarbons
- Hydrocerussite
- Hydrogen
- Hydrogeology
- Hydrolysis
- Hydrothermal
- Hydrothermal veins
- Hydrothermal vent
- Hydroxides
- Hydrozincite
- Hypersaline
- Iceberg
- Ice sheet
- Ichnology
- Ichnotaxa
- Ichnotaxon
- Idiomorphic
- Igneous
- Ignimbrite
- Ilmenite
- Ilvaite
- Index fossil
- Indium
- Indurated
- Infrared
- Inlier
- Inselberg
- Interbedded
- Intergrowth
- Interlocking
- Intrusion
- Invertebrate
- Iodargyrite
- Iodine
- Iranite
- Iridescent
- Iridium
- Iron
- Island arc
- Isometric
- Isomorphic
- Isotope
- Isotopic dating
- Isua Supracrustal Belt
- Jalpaite
- James Hutton
- Jarosite
- Joint
- Jurassic
- Jurbanite
- Ka
- Kame
- Kaolinite
- Karst
- Kartchner Caverns
- Kentrolite
- Kettle
- Kink
- Kink band
- Knap
- Konservat-Lagerstätten
- Krypton
- Kyanite
- Laccolith
- Lacuna
- Lagerstätten
- Lagoon
- Lahar
- Lamprophyre
- Lanarkite
- Landslide
- Landslip
- Langite
- Lanthanides
- Lanthanum
- Lapidary
- Laramide Orogeny
- Late Devonian Extinction
- Laumontite
- Lava
- Lawrencium
- Lead
- Leadhillite
- Lepidocrocite
- Leucocratic
- Libethenite
- Lignite
- Limestone
- Linarite
- Liquefaction
- Lithic fragment
- Lithification
- Lithium
- Lithologic unit
- Lithology
- Lithosphere
- Little Painted Desert
- Living cave
- Living fossil
- Lode
- Lode gold
- Loess
- Longshore drift
- Luster
- Lutetium
- Ma
- Maastrichtian
- Macquartite
- Macrofossil
- Mafic
- Magma
- Magnesio-hornblende
- Magnesium
- Magnetite
- Magnetite
- Malachite
- Malleable
- Malmesbury group
- Mammothite
- Manganese
- Manganite
- Mantle
- Marble
- Marguerite Thomas Williams
- Marine terrace
- Marinoan Glaciation
- Markascherite
- Marl
- Marquise Cut
- Mary Anning
- Mass extinction
- Massicot
- Massive
- Mass-movement
- Matlockite
- Meander
- Medium-grained
- Meitnerium
- Mélange
- Melanocratic
- Melanotekite
- Mendelevium
- Mercury
- Mesa
- Mescal Limestone
- Mesoarchean
- Mesocratic
- Mesoproterozoic
- Mesozoic
- Metallic
- Metallurgy
- Metamorphic
- Metamorphism
- Metapelite
- Metasedimentary
- Metasilicate
- Metatexis
- Metatorbernite
- Metatorbernite
- Metavolcanic
- Meteor Crater
- Mica
- Micaceous
- Microcline
- Microfossil
- Micrometer
- Micromount
- Micron
- Micropaleontology
- Mid-oceanic ridge
- Migmatite
- Mimetite
- Mine
- Mine Entrance
- Mineral
- Mineral classification
- Mineralization
- Mineral name
- Mineralogy
- Mineral species
- Mining
- Minium
- Miocene
- Miogeosyncline
- Mississippian
- Mixite
- Mogollon Rim
- Mohs scale
- Molasse
- Mold
- Molding
- Mollusca
- Molybdenite
- Molybdenum
- Monocline
- Monoclinic
- Montezuma Castle
- Montmorillonite
- Monument Valley
- Moraine
- Mordenite
- Morphological species concept
- Morphology
- Mosasaur
- Mottramite
- Mudflow
- Mudstone
- Mullion
- Munakataite
- Murdochite
- Muscovite
- Native element
- Nautiloid
- Nektonic
- Neoarchean
- Neodymium
- Neogene
- Neon
- Neontology
- Neoproterozoic
- Neotocite
- Neptunium
- Nickel
- Niobium
- Niter
- Nitrates
- Nitrocalcite
- Nitrogen
- Nobelium
- Nodule
- Non-clastic
- Nontronite
- Normal fault
- Notochord
- Nugget
- Nukundamite
- Oak Creek Canyon
- Obsidian
- Octahedral
- Offretite
- Oily
- Oligocene
- Oligoclase
- Olivenite
- Olivine
- Omori's Law
- Oolith
- Oolitic
- Oolitic limestone
- Opal
- Ordovician
- Ordovician-Silurian Extinction
- Ore
- Orogenesis
- Orogeny
- Orpiment
- Orthoclase
- Orthogeosyncline
- Orthorhombic
- Orthoserpierite
- Orthosilicate
- Osmium
- Ostracod
- Ostracoderm
- Othniel Charles Marsh
- Outcrop
- Oval Cut
- Overburden
- Oxbow lake
- Oxidation
- Oxygen
- Pahoehoe
- Painted Desert and Petrified Forest
- Palagonite
- Paleoanthropology
- Paleoarchean
- Paleoart
- Paleobathymetry
- Paleobiogeography
- Paleobiology
- Paleoceanography
- Paleocene
- Paleoclimate
- Paleocurrent
- Paleoenvironment
- Paleogene
- Paleogeography
- Paleomagnetism
- Paleoneurology
- Paleontological species concept
- Paleontologist
- Paleontology
- Paleoproterozoic
- Paleosol
- Paleozoic
- Palladium
- Palygorskite
- Palynology
- Pangea
- Paralaurionite
- Paratacamite
- Pear Cut
- Pearly
- Pebbles
- Pegmatite
- Pelagic
- Pelite
- Pennsylvanian
- Pentagonal
- Peridotite
- Period
- Perlite
- Permian
- Permo-Carboniferous
- Petrify
- Petroleum
- Petrology
- Phanerozoic
- Phenoclast
- Phenocryst
- Phlogopite
- Phoenicochroite
- Phosgenite
- Phosphate
- Phosphohedyphane
- Phosphorescence
- Phosphorus
- Photosynthesis
- Phyllite
- Phyllonite
- Phyllosilicate
- Pickeringite
- Piedmont
- Piemontite
- Piercing point
- Pillar
- Pillow lava
- Pinal County Minerals
- Pinalite
- Pioneer Formation
- Pitchstone
- Placer gold
- Placoderms
- Plagioclase
- Plancheite
- Planetesimals
- Plankton
- Planktonic
- Plateau
- Plate tectonics
- Platinum
- Plattnerite
- Platy
- Playa
- Pleistocene
- Pliocene
- Plumbonacrite
- Plumbotsumite
- Plumose
- Plumose structure
- Plutonic
- Plutonium
- Pneumatolysis
- Polonium
- Polybasite
- Polymictic
- Porcelaneous
- Porosity
- Porous
- Porphyroblast
- Porphyry
- Potassium
- Powellite
- Praseodymium
- Precambrian
- Precious Gem
- Precipitate
- Princess Cut
- Prism
- Prograde metamorphism
- Prokaryotic
- Promethium
- Property
- Protactinium
- Proterozoic
- Protist
- Protolith
- Proustite
- Psammite
- Pseudoboleite
- Pseudobrookite
- Pseudomalachite
- Pseudomatrix
- Pterodactyl
- Pterosaur
- Pulverulent
- Pumice
- Pygidium
- Pyramidal
- Pyrargyrite
- Pyrite
- Pyritohedron
- Pyroclastic
- Pyroclastic flow
- Pyrolusite
- Pyromorphite
- Pyrophyllite
- Pyroxene
- Pyroxenite
- Pyrrhotite
- Quarry
- Quarrying
- Quartz
- Quartzite
- Quartz Varieties
- Quaternary
- Queitite
- Radiant Cut
- Radiated
- Radiations
- Radium
- Radon
- Ramsdellite
- Rare earths
- Ray Grant
- Realgar
- Re-crystallization
- Red bed
- Reef
- Regional metamorphism
- Reniform
- Resinous
- Resurgent Caldera
- Reticulate
- Reticulated
- Retrograde metamorphism
- Reverse fault
- Reworked
- Rhenium
- Rhizopod
- Rhodium
- Rhodochrosite
- Rhombic
- Rhomboclase
- Rhombohedral
- Rhyolite
- Richard Owen
- Rift
- Rift valley
- Rio Grande Rift
- Ripple marks
- Roche moutonnée
- Rock
- Rock fall
- Rock-forming minerals
- Rock salt
- Rodinia
- Roentgenium
- Romanèchite
- Rosasite
- Rose Cut
- Rosette
- Round Brilliant Cut
- Rounded
- Rubidium
- Rudaceous
- Rudist
- Rudite
- Rugose
- Ruthenium
- Rutherfordium
- Rutile
- Saccharoidal
- Saldanian orogeny
- Saltation
- Samarium
- San Andreas fault
- Sand
- Sand
- Sandstone
- San Francisco Peaks
- Sanidine
- Santonian
- Sauconite
- Sauropod
- Sauropodomorph
- Scaly
- Scandium
- Scanning Electron Microscope
- Scheelite
- Schist
- Schistose
- Schorl
- Scolecite
- Scoria
- Scree
- Seaborgium
- Sea-stack
- Sectile
- Sediment
- Sedimentary layers
- Sedimentary rock
- Sediment trap
- Sedona
- Selenium
- SEM
- Semi-Precious Gem
- Sequence
- Sericite
- Series
- Serpentine
- Serpierite
- Shale
- Shannonite
- Shark Bay
- Shattuckite
- Shear zone
- Sheen
- Shield
- Shield Volcano Caldera
- Shingle beach
- Siberian Traps
- Siderite
- Sierra Madre Oriental
- Signor-Lipps effect
- Silcrete
- Silica
- Silicates
- Silicon
- Silky
- Sill
- Sillimanite
- Silt
- Siltstone
- Silurian
- Silver
- Skeletal
- Slate
- Slaty cleavage
- Slickenside
- Slump
- Smithsonite
- Snowball Earth
- Sodium
- Soil creep
- Soil liquefaction
- Soluble
- Solution load
- Solution weathering
- Sorting
- Spalling
- Spalling
- Specific gravity
- Specimen
- Speleothem
- Spessartine
- Sphalerite
- Sphene
- Spheroidal Weathering
- Spherulitic
- Splintery
- Spodumene
- Spongy
- Stalactite
- Stalactitic
- Stalagmite
- Starkeyite
- Staurolite
- Stellate
- Stolzite
- Stone
- Storm ridge
- Strain
- Strata
- Stratigraphy
- Streak
- Strike-slip fault
- Stromatolite
- Stromeyerite
- Strontium
- Sturtian Glaciation
- Subperiod
- Subterranean
- Subtropical
- Subvitreous
- Sulfates
- Sulfides
- Sulfosalts
- Sulfur
- Sulphur
- Sunset Crater
- Surficial
- Surite
- Suspension load
- Suture
- Syenite
- Syncline
- Syntaxis
- Szomolnokite
- Table Mountain Group
- Tabular
- Tabulate
- Talc
- Talus
- Tantalum
- Taxonomy
- Technetium
- Tectonic forces
- Tectonic plate
- Tectonic Plates
- Tektite
- Tellurium
- Tenacity
- Tenorite
- Tension
- Tephra
- Terbium
- Terrestrial
- Tertiary
- Tethys
- Tetragonal
- Tetrahedrite
- Tetrahexahedron
- Texture
- Thallium
- Thomsonite-Ca
- Thorium
- Thrust fault
- Thulium
- Thumbnail specimen
- Till
- Tillite
- Tin
- Titanite
- Titanium
- Todorokite
- Tonian
- Topaz
- Topography
- Tor
- Torbernite
- Tough
- Tourmaline
- Trace fossil
- Trachyte
- Traction load
- Transport
- Travertine
- Treatise on Invertebrate Paleontology
- Tremolite
- Triassic
- Triassic-Jurassic Extinction
- Triclinic
- Trillion Cut
- Trilobite
- Trisoctahedron
- Tropical
- Tsumebite
- Tuff
- Tufted
- Tundra
- Tungstates
- Tungsten
- Turbidite
- Turbidity current
- Turonian
- Turquoise
- Twin crystal
- Twinning
- Tygerberg formation
- Tyrolite
- Ultramafic
- Ultraviolet
- Unconformity
- Undulating hills
- Uplift
- Uraninite
- Uranium
- Urgonian
- Vacuole
- Valanginian
- Vanadates
- Vanadinite
- Vanadium
- Variety
- Variscan orogeny
- Varve
- Vauquelinite
- Vein
- Veinlet
- Vendian
- Vent
- Vergence
- Vermiculite
- Vermiculite
- Vertebrates
- Vesicle
- Vesiculated
- Vésigniéite
- Victorian Age
- Viscosity
- Viscous
- Vitreous
- Vitrophyre
- Volcanic ash
- Volcanic bomb
- Volcanic gases
- Volcano
- Voltaite
- Vug
- Wad
- Wave-cut platform
- Waxy
- Weathering
- Wherryite
- Wiggle trace
- Wiry
- Wittichenite
- Wolframite
- Wollastonite
- Wulfenite
- Wurtzite
- Xenolith
- Xenon
- Xenotime
- X-ray diffraction
- X-ray fluorescence
- Xyloid coal
- Yedlinite
- Yellow cake
- Yellowstone Caldera
- Yosemite Valley
- Young's modulus
- Ypresian
- Ytterbium
- Yttrium
- Zeolite
- Zinc
- Zircon
- Zircon
- Zirconium
- Zoisite
- Zunyite