Sedimentary Rock (Specifically A Clastic Sedimentary Rock Formed Into A Cobble)

Chert (Red Jasper variant)

Microcrystalline Quartz (SiO2)

Greywacke (River Slikkenstone)

Greywacke (Impure Sandstone)

Chert (Iron-stained River Cobble)

Microcrystalline Quartz (SiO2)

Granite Gneiss

Gneiss (High-grade regional metamorphic rock)

Chert / Flint

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Coquina

Biogenic Limestone (Calcium Carbonate, CaCO3)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Clear Quartz (or Rock Crystal)

Quartz (SiO₂)

Mookaite Jasper

Silicon Dioxide (SiO2) with iron oxide impurities

Chert (Yellow Jasper variant)

Microcrystalline Quartz (SiO2)

Labradorite (a variety of Feldspar)

Labradorite; (Na,Ca)(Al,Si)4O8 (a plagioclase feldspar)

Limestone (Porous/Travertine variant)

Sedimentary Calcium Carbonate (CaCO3)

Ironstone with Pyrite

Ferruginous Sandstone (Fe2O3) with minor Sulfide minerals (FeS2)

Quartz (vein quartz)

SiO2 (Silicon Dioxide)

Sandstone Concretion with Fossil Wood

Ferruginous Sandstone Concretion (SiO2 with Fe2O3 cement)

Almandine Garnet

Iron aluminum silicate (Fe3Al2(SiO4)3)

Favosites Fossil (Honeycomb Coral)

Favosites sp. (Extinct genus of tabulate coral)

Fossilized Crinoid Stem

Class Crinoidea (Echinodermata)

Orthoceras Fossil in Limestone

Orthoceras regulare (Class Cephalopoda; Order Orthocerida)

Travertine (Tufa)

Calcium Carbonate (CaCO3)

Mica Schist with Pyrite

Muscovite/Biotite Schist with Iron Sulfide (FeS2)

Chert (specifically Flint)

Silicon Dioxide (SiO2)

Chert (Iron-Stained)

Microcrystalline Quartz (SiO2)

Petrified Wood

Silicified Wood (primarily SiO2)

Chalcedony (specifically Agate or Water-worn Quartzite)

Silicon Dioxide (SiO2)

Coral Rock (Coquina)

Biogenic Limestone (Calcium Carbonate - CaCO3)

Chert (specifically as a lithic artifact/projectile point)

Chert (Silicon dioxide, SiO2)

Sandstone

Quartz Arenite (a type of sandstone composed of more than 90% quartz)

Quartz (specifically Milky Quartz/Quartzite)

Silicon Dioxide (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Chert (specifically Flint)

Microcrystalline or cryptocrystalline Quartz (SiO2)

River Rock (Basalt/Greywacke)

Aphanitic Basalt or Lithic Sandstone (Greywacke)

Gowganda Tillite (Puddingstone)

Glacial Diamictite (Gowganda Formation)

Banded Gneiss

Gneiss (High-grade regional metamorphic rock)

Chert (specifically Flint or Jasper variant)

Silicon Dioxide (SiO2)

Rock Crystal Quartz

Quartz (SiO₂)

Sandstone Concretion

Clastic Sedimentary Concretion (typically Quartz/Silica with Iron Oxide)

Slate

Foliated Metamorphic Rock (primarily composed of quartz, illite, and chlorite)

Pink Opal

Hydrated Amorphous Silica (SiO2·nH2O)

Chert (specifically a Worked Flint/Knapped Flake)

Chert / Flint (Microcrystalline Quartz, SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Sandy Ironstone

Ferruginous Sandstone