silicified

Tetradium sp. (a.k.a. Prismostylus sp.) (Elkhorn Formation, Upper Ordovician; south of Dayton, Ohio, USA) 1
by James St. John

Labechia sp. (fossil stromatoporoid sponge) (Elkhorn Formation, Upper Ordovician; south of Dayton, Ohio, USA) 8
by James St. John

Labechia sp. (fossil stromatoporoid sponge) (Elkhorn Formation, Upper Ordovician; south of Dayton, Ohio, USA) 7
by James St. John

Quartz-pebble conglomerate ("Sharon Conglomerate", Lower Pennsylvanian; Jackson North roadcut, Ohio, USA) 41
by James St. John

Labechia sp. (fossil stromatoporoid sponge) (Elkhorn Formation, Upper Ordovician; south of Dayton, Ohio, USA) 3
by James St. John

Labechia sp. (fossil stromatoporoid sponge) (Elkhorn Formation, Upper Ordovician; south of Dayton, Ohio, USA) 5
by James St. John

Quartz-pebble conglomerate ("Sharon Conglomerate", Lower Pennsylvanian; Jackson North roadcut, Ohio, USA) 37
by James St. John

Stromatoporoid fossil (Columbus Limestone, Middle Devonian; Columbus, Ohio, USA)
by James St. John

Oolitic chert (Gatesburg Formation, Upper Cambrian; State College, Pennsylvania, USA) 4
by James St. John

Partially silicified Hexagonaria (fossil coral) (Columbus Limestone, Middle Devonian; Emerald Parkway roadcut, Dublin, Ohio, USA) 1
by James St. John

Intraclastic limestone (Columbus Limestone, Middle Devonian) 2
by James St. John

Silicified rugose corals in fossiliferous limestone (Honaker Trail Formation, Upper Pennsylvanian; Grand County, Utah, USA) 4
by James St. John

Tree Hoodoo
by zeesstof

"Turritella Agate" (fossiliferous chertified limestone) (Laney Member, Green River Formation, Middle Eocene; near Wamsutter, Wyoming, USA) 5
by James St. John

Labechia sp. (fossil stromatoporoid sponge) encrusting a cephalopod (Elkhorn Formation, Upper Ordovician; south of Dayton, Ohio, USA)
by James St. John

Quartz-pebble conglomerate ("Sharon Conglomerate", Lower Pennsylvanian; Jackson North roadcut, Ohio, USA) 38
by James St. John

Stromatoporoid in limestone (Columbus Limestone, Middle Devonian; abandoned quarry, Kelleys Island, Lake Erie, Ohio, USA) 1
by James St. John

Agatized coral point (Florida, USA) 6
by James St. John

Equisetum (Equisetum) telmateia Ehrhart 1783 (Equisetales Equisetaceæ Equisetoideæ); Hedera helix Linnæus 1753 (Apiales Araliaceæ Aralioideæ); Bromus (Stenobromus) sterilis Linnæus 1753 (Poales Poaceæ Pooideæ Bromeæ)
by photos 1–1000

Furcaster paleozoicus fossil brittle star (Kaub Formation, Hunsrück Slate Group, Lower Devonian; Budenbach area, western Germany) 1
by James St. John

Quartz-pebble conglomerate ("Sharon Conglomerate", Lower Pennsylvanian; Jackson North roadcut, Ohio, USA) 39
by James St. John

Concretionary cone-in-cone structures (Benton Shale, Upper Cretaceous; Red Rock Canyon Open Space, Colorado Springs, Colorado, USA) 8
by James St. John

Opalite-chert with cinnabar (Silver Chief Mine, Battle Mountain, Nevada, USA) 1
by James St. John

Interbedded metagraywacke-slate (Lake Vermilion Formation, Neoarchean, 2.695-2.722 Ga; Pike River Bridge outcrop, just north of Peyla, Minnesota, USA) 3
by James St. John

Opalite-chert with cinnabar (Silver Chief Mine, Battle Mountain, Nevada, USA) 5
by James St. John

Rainy Butte Flint (Sentinel Butte Formation, Upper Paleocene; North Dakota, USA) 2
by James St. John

Opalite-chert with cinnabar (Silver Chief Mine, Battle Mountain, Nevada, USA) 7
by James St. John

Fossiliferous asphaltic limestone (Buckhorn Asphalt, Middle Pennsylvanian; Buckhorn Asphalt Quarry, Oklahoma, USA) 3
by James St. John

Interbedded metagraywacke-slate (Lake Vermilion Formation, Neoarchean, 2.695-2.722 Ga; Pike River Bridge outcrop, just north of Peyla, Minnesota, USA) 13
by James St. John

Araucarioxylon arizonicum (fossil wood) (Chinle Formation, Upper Triassic; south of Adamana, Arizona, USA) 3
by James St. John

Cone-in-cone structures (Whitewood, South Dakota, USA) 2
by James St. John

Interbedded metagraywacke-slate (Lake Vermilion Formation, Neoarchean, 2.695-2.722 Ga; Pike River Bridge outcrop, just north of Peyla, Minnesota, USA) 4
by James St. John

Silicified rugose corals in fossiliferous limestone (Honaker Trail Formation, Upper Pennsylvanian; Grand County, Utah, USA) 3
by James St. John

Halysites louisvillensis fossil coral (Louisville Limestone, upper Middle Silurian to lower Upper Silurian; Jefferson County, Kentucky, USA)
by James St. John

Columbus Limestone (Middle Devonian; Emerald Parkway roadcut, Dublin, Ohio, USA) 1
by James St. John

Interbedded metagraywacke-slate (Lake Vermilion Formation, Neoarchean, 2.695-2.722 Ga; Pike River Bridge outcrop, just north of Peyla, Minnesota, USA) 12
by James St. John

Paraspirifer bownockeri (pyritized fossil brachiopod) (Silica Formation, Middle Devonian; quarry in Lucas County, Ohio, USA) 14
by James St. John

Quartz-pebble conglomerate ("Sharon Conglomerate", Lower Pennsylvanian; Jackson North roadcut, Ohio, USA) 42
by James St. John

Weathered, oxidized pyrite (Columbus Limestone or Delaware Limestone, Middle Devonian; Emerald Parkway roadcut, Dublin, Ohio, USA) 4
by James St. John

Fossiliferous limestone (Columbus Limestone, Middle Devonian; Emerald Parkway roadcut, Dublin, Ohio, USA) 18
by James St. John

Silicified rugose corals in fossiliferous limestone (Honaker Trail Formation, Upper Pennsylvanian; Grand County, Utah, USA) 2
by James St. John

Joint in limestone (Columbus Limestone, Middle Devonian; Indian Village Canyon, Columbus, Ohio, USA) 2
by James St. John

Stromatolite in silicified metadolostone (Kona Dolomite, Paleoproterozoic, 2.2 to 2.3 Ga; County Road 480 roadcut, Ragged Hills, Upper Peninsula of Michigan, USA) 1
by James St. John

Archaeocyathan limestone (Ajax Limestone, Lower Cambrian; Ajax Mine, South Australia) 32
by James St. John

Stromatolite (Kona Dolomite, Paleoproterozoic, 2.2-2.3 Ga; Marquette, Michigan, USA)
by James St. John

Stromatoporoid (Ashlock Formation, Upper Ordovician; Paint Lick Elementary School outcrop, Garrard County, Kentucky, USA) 31
by James St. John

Silicified coral fossils (Middle Devonian; Auglaize Quarry, near Junction, Ohio, USA) 4
by James St. John

Stromatoporoid (Ashlock Formation, Upper Ordovician; Paint Lick Elementary School outcrop, Garrard County, Kentucky, USA) 11
by James St. John

Stigmaria fossil root (Newark, Ohio, USA) 1
by James St. John

Agatized coral (Tertiary; Withlacoochee River, Georgia, USA) 2
by James St. John

Partially silicified rugose coral in limestone (Columbus Limestone, Middle Devonian; Emerald Parkway roadcut, Dublin, Ohio, USA)
by James St. John

Concretionary cone-in-cone structures (Benton Shale, Upper Cretaceous; Red Rock Canyon Open Space, Colorado Springs, Colorado, USA) 16
by James St. John

Stromatoporoid (Ashlock Formation, Upper Ordovician; Paint Lick Elementary School outcrop, Garrard County, Kentucky, USA) 5
by James St. John

Brachiopods in fossiliferous limestone (Jeffersonville Limestone, Middle Devonian; Falls of the Ohio, southern Indiana, USA) 2
by James St. John

Moellerina greenei (fossil charophyte oogonia) in fossiliferous limestone (Columbus Limestone, Middle Devonian; Emerald Parkway roadcut, Dublin, Ohio, USA) 1
by James St. John

Striated cone-in-cone limestone (likely an interbed from the Ohio Shale, Upper Devonian; creek bed of an Alum Creek tributary, northern Delaware County, Ohio, USA) 6
by James St. John

Delaware Limestone over Columbus Limestone (Middle Devonian; Griggs Dam, Columbus, Ohio, USA) 5
by James St. John

Mookaite (Windalia Radiolarite Formation, Lower Cretaceous; Western Australia) 21
by James St. John

Ferruginous quartz-pebble & lithic conglomerate (derived from boulder in "Sharon Conglomerate", Lower Pennsylvanian; Jackson North roadcut, Ohio, USA) 32
by James St. John

Columbus Limestone (Middle Devonian) (Hayden Falls, Dublin, Ohio, USA) 2
by James St. John