Rock (Likely Sedimentary)

Sandstone Pebble

Arenite (SiO2 based)

Dark limestone or mudstone pebble with calcite veins

Fine-grained carbonate rock, likely limestone (dominantly calcite, CaCO₃); exact identification requires testing

Concretion (likely ironstone or carbonate)

Sedimentary concretion; exact mineral composition cannot be determined from the image

Likely quartz-rich sedimentary pebbles

Quartz arenite or chert-like siliceous rock; exact identification is uncertain from the photograph

Sandstone (likely Calcareous or Micaceous)

Clastic sedimentary rock (primarily Quartz with Cementing Agents)

River Quartzite Siltstone

Quartz-rich Meta-siltstone (SiO2 dominated)

Likely blue-gray gneiss

Gneiss, a foliated metamorphic rock; exact mineral composition cannot be confirmed from the image

Flagstone (likely sandstone or slate)

Flagstone is a paving form, not a single rock species; likely thin-bedded sandstone, with possible slate pieces

Iron-stained rock, likely limonite-rich weathered stone

Limonite (iron oxyhydroxides, chiefly goethite) coating or staining a rock of uncertain composition

Likely beach-worn pebbles

Lithified rock fragments; exact rock type cannot be determined from the photo

Fossiliferous Shale

Sedimentary Clastic Rock with fossil inclusions (likely Brachiopod or Bivalve impressions)

Mixed tumbled river pebbles and beach stones

Polymictic alluvial gravel; components include quartz, chert, jasper, sandstone, and altered volcanic rocks

Banded gneiss

Foliated gneiss, likely quartz–feldspar–mica gneiss

Weathered ironstone pebble

Iron-oxide-cemented sediment, likely limonite/goethite-rich; exact identification cannot be confirmed from the image alone

Likely fine-grained sandstone pebble

Quartz-rich sandstone; exact composition cannot be confirmed from the image

Likely bituminous coal

Coal, predominantly carbon-rich organic matter; exact rank cannot be confirmed visually

Fossil shell, likely a brachiopod or bivalve

Uncertain from the photograph; possibly a ribbed brachiopod or marine bivalve fossil

Quartz fragment

Quartz (silicon dioxide, SiO₂)

Sedimentary Pebble (Sandstone)

Clastic Sedimentary Rock (SiO2 dominant)

Sandstone (likely Quartzose)

Arenite

Pebble or Cobble (likely composed of sandstone or conglomerate)

Clastic Sedimentary Rock (specific name like sandstone, conglomerate, or breccia would require microscopic analysis of clast size and angularity)

River Stone (likely Andesite or Siltstone)

Intermediate Volcanic Rock / Fine-grained Sedimentary Rock

Sandstone (Calcareous Sandstone)

Calcareous Sandstone (primarily SiO2 with CaCO3 cement)

Rounded gray-brown pebble

Indeterminate; likely weathered quartz-rich sandstone or fine-grained volcanic rock

Chert (Jasper/Agate mix)

Microcrystalline Quartz (SiO2)

Blue Chalcedony (likely dyed Agate)

Silicon Dioxide (SiO₂)

Coal (likely Bituminous or Lignite)

Organic Sedimentary Rock (Carbonaceous)

Fossiliferous Sandstone (with Brachiopod or Bivalve mold)

Clastic Sedimentary Rock with Macrofossil Mold

Likely sandstone

Quartz-rich sandstone (composition cannot be confirmed from the photo)

Sandstone

Arenite (SiO2 primarily)

Limestone with Lichen

Carbonate Sedimentary Rock (primarily CaCO3)

Banded river pebble

Likely banded sandstone or siltstone; exact identification requires testing

Blue-gray stone fragment, possibly slate or fine-grained basalt

Undetermined; appearance is consistent with slate (fine-grained metamorphosed mudstone), but the image is insufficient for reliable identification.

Chert Arrowhead (Lithic Artifact)

Chert (Cryptocrystalline Quartz, SiO2)

Iron-rich sedimentary rock, likely banded iron formation fragment

Banded iron formation (BIF), composed chiefly of hematite/magnetite and chert

Quartz (Chert/Chalcedony variety)

Silicon Dioxide (SiO2)

Weathered gray slate or phyllite pebble

Fine-grained, foliated metamorphic rock; exact identification requires closer examination

Rounded river pebble, likely altered limestone or sandstone

Probable micritic limestone (calcite-rich, CaCO₃) or fine-grained sandstone

Small rounded pebble, likely sandstone or weathered limestone

Indeterminate clastic carbonate/siliciclastic pebble; mineral composition appears dominated by quartz, feldspar, and/or calcite

Small shell fragment (likely gastropod or bivalve fossil)

Fossilized calcium-carbonate shell; chiefly aragonite or calcite (CaCO₃)

Tumbled clear quartz

Quartz (silicon dioxide, SiO₂)

Sandstone (with Chert/Quartzite)

Arenite (SiO2 primarily)