Rock (Likely Sedimentary)

Sandstone with Lichen and Iron Oxide Staining

Quartz Arenite / Sandstone

Limestone

Calcium Carbonate (CaCO3)

Milky quartz with iron-oxide staining

Quartz (silicon dioxide, SiO₂)

Granite

Phaneritic Plutonic Felsic Rock (SiO2, KAlSi3O8, NaAlSi3O8, CaAl2Si2O8)

Garnet (almandine or pyrope variety)

Silicate mineral Group: (Fe, Mg, Mn, Ca)3(Al, Fe, Cr)2(SiO4)3

Quartz Pebble

Silicon Dioxide (SiO2)

Chert (Common Opal variant)

Silicon Dioxide (SiO2)

Basalt with Quartz/Calcite Inclusions

Mafic Volcanic Rock (Fe-Mg silicate rich)

Basalt (River Stone)

Basalt (Aphanitic Mafic Igneous Rock)

Porphyritic Basalt

Amygdaloidal Porphyritic Basalt

Gravel (likely Basalt or Greywacke)

Basalt (Mafic volcanic rock)

Weathered green-gray stone, likely serpentinite or chlorite-rich metamorphic rock

Probable serpentinite (antigorite–lizardite), possibly chlorite schist or altered basalt

Granite

Phaneritic intrusive igneous rock

Granite

Phaneritic Plutonic Felsic Rock

Fossilized Echinoid

Echinoidea (likely of the order Echinoidea)

Sandstone (likely Arkose)

Arenite (Feldspathic Sandstone / Arkose)

Granitic Quartz with Feldspar

Granite (composed primarily of SiO2 and KAlSi3O8)

Limestone (River Stone)

Calcium Carbonate (CaCO3)

Brachiopod Fossil

Phylum Brachiopoda

Quartz-rich pegmatitic rock, possibly rose quartz with mica

Granitic pegmatite; predominantly quartz (SiO₂), with feldspar and mica

River Cobble (likely Basalt)

Mafic Igneous Rock (Aphanitic)

Agate (specifically Carnelian or Honey Agate)

Silicon Dioxide (SiO2)

Sandstone

Arenite (SiO2 dominant)

Likely weathered basalt or dark volcanic rock

Basalt; primarily plagioclase feldspar and pyroxene, with possible olivine and iron oxides

Garnet (likely Almandine or Pyrope)

Garnet (Group Name), Fe3Al2(SiO4)3 or Mg3Al2(SiO4)3

Iron-rich quartzite or limonite-bearing rock

Quartzite (SiO₂) with iron oxides/hydroxides, chiefly hematite and goethite

Small polished brown stone

Indeterminate; possibly tumbled jasper, brown agate, or another iron-stained silicate

Yellow Chert (Gold-colored River Pebble)

Microcrystalline Quartz (SiO2) with Limonite/Goethite staining

Polished granite pebble

Granite, commonly quartz–feldspar–mica aggregate

Pyrite (likely)

Iron disulfide, FeS₂; commonly called fool’s gold

Quartz pebble

Silicon dioxide (SiO2)

Iron Meteorite (likely Chondrite or weathered Iron-Nickel)

Meteorite (Fe-Ni alloy & silicates)

Quartz pebble with surface markings

Silicon Dioxide (SiO2)

Conchoidal Basalt Pebble

Basalt with conchoidal fracturing

Quartz Geode

Quartz (Silicon Dioxide, SiO2)

Basalt Pebble with Vesicles

Vesicular Basalt

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Milky Quartz (Water-worn Pebble)

Silicon Dioxide (SiO2)

Chert (specifically Jasper or Flint)

Cryptocrystalline Quartz (SiO2)

Fossiliferous Limestone

Bioclastic Limestone (with Brachiopod and Bivalve molds)

Tumbled sandstone pebble

Quartz-rich sandstone, commonly subarkose or arkose