silicified

Fossiliferous limestone (Columbus Limestone, Middle Devonian; Olentangy River at Lazarus Run confluence, Delaware County, Ohio, USA) 1
by James St. John

Columbus Limestone (Middle Devonian; Emerald Parkway roadcut, Dublin, Ohio, USA) 11
by James St. John

Cone-in-cone limestone bed (probably from an interbed in the Ohio Shale, Upper Devonian; central Ohio, USA) 1
by James St. John

Silicified rugose corals in limestone (Columbus Limestone, Middle Devonian; Quarry Trails Park, Columbus, Ohio, USA) 4
by James St. John

Gastropod internal mold (Columbus Limestone, Middle Devonian; abandoned quarry, Kelleys Island, Lake Erie, Ohio, USA) 6
by James St. John

Rainy Butte Flint (Sentinel Butte Formation, Upper Paleocene; North Dakota, USA) 90
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) 3
by James St. John

Silicified rugose corals in limestone (Columbus Limestone, Middle Devonian; Quarry Trails Park, Columbus, Ohio, USA) 2
by James St. John

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

Stromatoporoid fragments (Ashlock Formation, Upper Ordovician; Paint Lick Elementary School outcrop, Garrard County, Kentucky, USA) 23
by James St. John

Stromatoporoid (Ashlock Formation, Upper Ordovician; Paint Lick Elementary School outcrop, Garrard County, Kentucky, USA) 29
by James St. John

Cone-in-cone limestone bed (interbed in the Ohio Shale, Upper Devonian; Glen Echo Ravine, Columbus, central Ohio, USA)
by James St. John

Delaware Limestone over Columbus Limestone (Middle Devonian; Indian Village Canyon, Columbus, Ohio, USA) 5
by James St. John

Ferruginous quartz-pebble conglomerate (derived from boulder in "Sharon Conglomerate", Lower Pennsylvanian; Jackson North roadcut, Ohio, USA) 30
by James St. John

Fossil brachiopod in limestone (Columbus Limestone, Middle Devonian; Quarry Trails Park, Columbus, Ohio, USA) 2
by James St. John

Silicified rugose corals in limestone (Columbus Limestone, Middle Devonian; Quarry Trails Park, Columbus, Ohio, USA) 3
by James St. John

Fossiliferous limestone (Columbus Limestone, Middle Devonian; Emerald Parkway roadcut, Dublin, Ohio, USA) 20
by James St. John

Paraspirifer bownockeri (pyritized fossil brachiopod) (Silica Formation, Middle Devonian; quarry in Lucas County, Ohio, USA) 13
by James St. John

Coral in fossiliferous limestone (Jeffersonville Limestone, Middle Devonian; Falls of the Ohio, southern Indiana, USA) 30
by James St. John

Weathered, oxidized pyrite (Columbus Limestone or Delaware Limestone, Middle Devonian; Emerald Parkway roadcut, Dublin, Ohio, USA) 3
by James St. John

Fossiliferous dolostone (Rockford Limestone, Lower Mississippian; Burkesville West Rt. 90 roadcut, Kentucky, USA) 12
by James St. John

Mookaite (Windalia Radiolarite Formation, Lower Cretaceous; Western Australia) 11
by James St. John

Furcaster paleozoicus fossil brittle star (Kaub Formation, Hunsrück Slate Group, Lower Devonian; Budenbach area, western Germany) 2
by James St. John

Fossil nautiloid shell with original iridescent nacre in fossiliferous asphaltic limestone (Buckhorn Asphalt, Middle Pennsylvanian; Buckhorn Asphalt Quarry, Oklahoma, USA) 2
by James St. John

Fossiliferous limestone (Jeffersonville Limestone, Middle Devonian; Falls of the Ohio, southern Indiana, USA) 29
by James St. John

Fossiliferous limestone (Jeffersonville Limestone, Middle Devonian; Falls of the Ohio, southern Indiana, USA) 30
by James St. John

Mudshale clast in quartz-pebble conglomerate ("Sharon Conglomerate", Lower Pennsylvanian; Jackson North roadcut, Ohio, USA) 56
by James St. John

Chert nodule horizon in fossiliferous limestones (Columbus Limestone, Middle Devonian; Marblecliff Quarry, Hilliard, Ohio, USA)
by James St. John

Columbus Limestone (Middle Devonian; Emerald Parkway roadcut, Dublin, Ohio, USA) 3
by James St. John

Stromatoporoid fragments (Ashlock Formation, Upper Ordovician; Paint Lick Elementary School outcrop, Garrard County, Kentucky, USA) 22
by James St. John

White fossiliferous chert in limestone (Columbus Limestone, Middle Devonian; Emerald Parkway roadcut, Dublin, Ohio, USA) 3
by James St. John

Cystiphylloides americanum (fossil coral) (Columbus Limestone, Middle Devonian; Delaware County, Ohio, USA) 4
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) 5
by James St. John

Fossiliferous limestone (Columbus Limestone, Middle Devonian; Emerald Parkway roadcut, Dublin, Ohio, USA) 15
by James St. John

Stromatoporoid (Ashlock Formation, Upper Ordovician; Paint Lick Elementary School outcrop, Garrard County, Kentucky, USA) 9
by James St. John

Slaty metadolostone (Kona Dolomite, Paleoproterozoic, 2.2 to 2.3 Ga; Marquette South Outcrop, Upper Peninsula of Michigan, USA)
by James St. John

White fossiliferous chert (Columbus Limestone, Middle Devonian; Emerald Parkway roadcut, Dublin, Ohio, USA) 2
by James St. John

Quartz-permineralized fossil wood 34
by James St. John

Mookaite (Windalia Radiolarite Formation, Lower Cretaceous; Western Australia) 14
by James St. John

Stromatoporoid fossil (Columbus Limestone, Middle Devonian; Ohio, USA) 1
by James St. John

Corals in fossiliferous limestone (Jeffersonville Limestone, Middle Devonian; Falls of the Ohio, southern Indiana, USA) 18
by James St. John

Ferruginous quartz-pebble conglomerate (derived from boulder in "Sharon Conglomerate", Lower Pennsylvanian; Jackson North roadcut, Ohio, USA) 24
by James St. John

Leptaena (fossil brachiopod) (Columbus Limestone, Middle Devonian; abandoned quarry, Kelleys Island, Lake Erie, Ohio, USA) 2
by James St. John

Archaeocyathan limestone (Ajax Limestone, Lower Cambrian; Ajax Mine, South Australia) 68
by James St. John

Fossiliferous asphaltic limestone (Buckhorn Asphalt, Middle Pennsylvanian; Buckhorn Asphalt Quarry, Oklahoma, USA) 4
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) 4
by James St. John

Fossiliferous asphaltic limestone (Buckhorn Asphalt, Middle Pennsylvanian; Buckhorn Asphalt Quarry, Oklahoma, USA) 10
by James St. John

Hot Creek Rhyolite Flow (Pleistocene, 288 or 333 ka; Hot Creek Gorge, Long Valley Caldera, California, USA) 9
by James St. John

Opalite-chert with cinnabar (Silver Chief Mine, Battle Mountain, Nevada, USA) 13
by James St. John

Weathered, oxidized pyrite (Columbus Limestone or Delaware Limestone, Middle Devonian; Emerald Parkway roadcut, Dublin, Ohio, USA) 2
by James St. John

Fossiliferous asphaltic limestone (Buckhorn Asphalt, Middle Pennsylvanian; Buckhorn Asphalt Quarry, Oklahoma, USA) 5
by James St. John

Brachiopod in limestone (Columbus Limestone, Middle Devonian; Griggs Dam, Columbus, Ohio, USA)
by James St. John

Delaware Limestone over Columbus Limestone (Middle Devonian; Marblecliff Quarry, Hilliard, Ohio, USA) 4
by James St. John

Paraspirifer bownockeri (pyritized fossil brachiopod) (Silica Formation, Middle Devonian; quarry in Lucas County, Ohio, USA) 3
by James St. John

Coiled nautiloid (Columbus Limestone, Middle Devonian; Ohio, USA)
by James St. John

Fossiliferous asphaltic limestone (Buckhorn Asphalt, Middle Pennsylvanian; Buckhorn Asphalt Quarry, Oklahoma, USA) 9
by James St. John

Stromatoporoid (Ashlock Formation, Upper Ordovician; Paint Lick Elementary School outcrop, Garrard County, Kentucky, USA) 26
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) 1
by James St. John

Archaeocyathan limestone (Ajax Limestone, Lower Cambrian; Mt. Scott Range, South Australia) 5
by James St. John

Fossiliferous asphaltic limestone (Buckhorn Asphalt, Middle Pennsylvanian; Buckhorn Asphalt Quarry, Oklahoma, USA) 12
by James St. John