Mineral, Sediment

Petrified Wood

Silicified Wood (SiO2 permineralization)

Fossilized tooth, possibly a shark tooth

Indeterminate fossil tooth; species cannot be identified from this view

Petrified Wood

Silicified Wood (SiO2)

Iron-rich banded rock, likely goethite/limonite-rich ironstone

Goethite (α-FeO(OH)) and/or limonite with iron-oxide-stained silica or clay; exact identification requires testing

Small tumbled pebble (likely quartz or feldspar)

Indeterminate; probable quartz (SiO₂) or feldspar

Fossilized Gastropod in Chert/Limestone

Internal mold of Gastropoda (Class) with CaCO3 or SiO2 mineral formula

Iron-rich concretion (possibly limonite/goethite)

Limonite, a mixture of iron oxyhydroxides, commonly including goethite (α-FeO(OH))

Rounded green-gray pebble, possibly serpentinite

Undetermined; appearance is consistent with serpentine-rich rock, but a photograph cannot confirm the mineral identification

Small dark pebble, possibly basalt or iron-rich stone

Undetermined; image alone cannot confirm composition

Banded Sandstone

Quartz-rich Arenite Sandstone

Sandstone

Arenite (SiO2 principal composition)

Fossilized Shark Tooth

Selachimorpha fossil

Fossilized tooth, likely mammalian molar

Silicified or mineral-replaced mammalian tooth; exact taxon cannot be determined from the image

Tiny amber-colored crystal or mineral fragment

Indeterminate from image; possibly quartz, citrine, topaz, or iron-stained feldspar

Petrified Wood

Silicified wood (Quartz/Chalcedony replacement of organic matter)

Sandstone Concretion

Moqui Marble / Ironstone Concretion (Iron oxide-cemented sandstone)

Banded Siltstone

Banded Siltstone / Laminated Siltstone

Rounded gray-green stone, likely fine-grained sandstone or siltstone

Indeterminate clastic sedimentary rock; exact identification requires closer examination

Tumbled river pebble, likely fine-grained sandstone or mudstone

Indeterminate lithic clast; possibly quartz-rich sandstone or siltstone

Fossilized Gastropod / Coral

Phylum Mollusca / Cnidaria (Silicified or Calcified)

Likely iron-rich sandstone or ironstone

Ferruginous sandstone/ironstone; exact identification is uncertain from the photograph

Amber jewelry (possibly amber-colored glass or resin)

Amber — fossilized plant resin, chiefly composed of polymerized terpenoids; the pictured material cannot be confirmed from the image

Gneiss pebble

Felsic banded gneiss, likely granitic in composition

Small rounded quartz pebble

Quartz (SiO₂), possibly milky quartz

Possible iron-oxide concretion with a dark mineral cap

Iron-oxide–cemented sedimentary concretion; exact composition cannot be determined from the image

Fossil Shell

Invertebrate fossil (Mollusca)

Granite pebble

Granite, a coarse-grained felsic intrusive igneous rock

Fossilized shell fragment

Likely a fossil mollusk shell; exact taxon cannot be determined from the image

Sand

Siliciclastic sediment / Quartz sand (SiO2)

Petrified Wood

Silicified Wood (primarily SiO2)

Likely tumbled brown mineral fragment

Indeterminate; possibly iron-stained quartz, jasper, or carnelian

Iron-rich weathered pebble

Likely limonite/goethite-bearing ferruginous rock; exact identification requires testing

Mixed small pebbles and mineral grains

Unidentified detrital sediment; likely quartz-, feldspar-, and lithic fragments

Quartz Sand Grain

Silicon Dioxide (SiO2)

Sandstone Cobble

Arenite (primarily Quartz Arenite)

Rounded gray-green beach cobble

Unidentified lithic cobble; exact rock type cannot be determined from the image

Sandstone Pebble

Arenite (SiO2 based)

Calamites

Calamites (Pith cast fossil)

Sandstone (Quartzose)

Arenite

Vein-filled Sedimentary Rock

Silicified sedimentary rock with quartz/calcite vein

Claystone Concretion

Septarian Concretion (Ironstone-rich)

Banded Sandstone

Clastic Sedimentary Rock (Quartz Arenite)