Organic Material (Likely A Fruit Or Berry)

Coquina

Biogenic Limestone (Calcium Carbonate, CaCO3)

Quartz-rich pebble, possibly chert or silicified limestone

Microcrystalline quartz (SiO₂), possibly chalcedony; exact identification is uncertain from the photograph

Polished dark green stone, likely nephrite jade or serpentine

Nephrite jade: tremolite–actinolite amphibole, Ca₂(Mg,Fe)₅Si₈O₂₂(OH)₂; possible serpentine: Mg₃Si₂O₅(OH)₄

Polished brown jasper (likely brecciated or orbicular jasper)

Microcrystalline quartz/chalcedony, SiO₂, with iron-oxide and other mineral inclusions

Tumbled hematite (likely hematite-rich ironstone)

Hematite, Fe₂O₃; possibly mixed with magnetite or goethite

Blue sodalite-bearing rock, likely sodalite in nepheline syenite

Sodalite (Na₈Al₆Si₆O₂₄Cl₂), possibly in nepheline syenite

Quartz

Silicon dioxide (SiO2)

Chert (Nodule)

Chert (primarily Microcrystalline Quartz - SiO2)

Megalodon Shark Tooth

Otodus megalodon

Chert (Flint)

Microcrystalline Quartz (SiO2)

Black Limestone with Calcite Veining

Limestone (CaCO3) with Calcite (CaCO3) inclusions

Chert (Flint)

Silicon Dioxide (SiO2)

Sandstone (likely Ferruginous)

Arenite (SiO2 based with Fe2O3/FeO(OH) cement)

Water-worn brown chert or jasper pebble

Microcrystalline quartz (SiO₂), likely ferruginous chert/jasper

Tumbled light-colored stone, possibly quartzite or limestone

Indeterminate; likely quartzite (mostly SiO₂) or calcitic limestone (CaCO₃)

Fossiliferous Sandstone / Fossil Fragment

Fossiliferous Sedimentary Matrix with Indeterminate Fossil Material

Chert (Chert Nodule)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Fossiliferous Limestone

Biogenic Limestone (Calcium Carbonate, CaCO3)

Polished orbicular jasper / brecciated jasper

Jasper, microcrystalline quartz (SiO₂), with iron-oxide and clay-rich inclusions

Ironstone Concretion / Goethite-Hematite Geode

Goethite / Hematite Concretion (Fe3O4 / FeO(OH) / Fe2O3)

Petrified Wood

Silicified wood (Quartz variant, SiO2)

Petrified Wood

Silicified Wood (SiO2)

Blue cabochon gemstone, likely sapphire

Corundum (Al₂O₃), blue variety colored mainly by iron and titanium

Weathered granite or granitic gneiss

Quartz–feldspar–mica granitoid; possibly gneiss if the visible layering is tectonic

Jasper (Mookaite variety likely)

Silicon Dioxide (SiO2) with iron oxide inclusions

Dalmatian jasper (likely orbicular microgranite)

Quartz–feldspar–biotite/pyroxene microgranite; commonly marketed as Dalmatian jasper

Weathered limestone or calcitic cave deposit

Calcite (CaCO₃), likely porous limestone/travertine

Quartzite

Metamorphic Quartzite (SiO2)

Rounded quartzite pebble

Quartzite, predominantly crystalline SiO₂

Quartzite Arrowhead (Archaeological Lithic)

Recrystallized Quartz (SiO2)

Tumbled jasper (likely ocean or orbicular jasper)

Microcrystalline quartz (chalcedony), SiO₂, with iron oxides and dark accessory minerals

Chert (Pebble)

Silicon Dioxide (SiO2)

Weathered quartz-rich cobble (probable quartzite or silicified rock)

Quartzite, predominantly SiO₂; exact identification is uncertain from the photograph

Quartzite with Hematite

Metamorphosed Quartz Sandstone (SiO2 with Fe2O3 inclusions)

Tumbled quartz pebble

Quartz (SiO₂), likely milky or fractured rock crystal

Tumbled orange calcite

Calcite (calcium carbonate, CaCO₃)

Likely tumbled quartz/chalcedony

Quartz (SiO₂), possibly milky quartz or pale chalcedony

Tumbled jasper (likely brecciated or orbicular jasper)

Microcrystalline quartz (chalcedony), SiO₂, with iron-oxide and other mineral inclusions

Likely weathered brown rock or iron-rich mineral specimen

Indeterminate from image; possible limonite/goethite-rich material

Weathered chert or siliceous limestone

Microcrystalline quartz (SiO₂), possibly with carbonate minerals

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood

Silicified Wood (SiO2)