Rock (Likely Sedimentary)

Sandstone (Ferruginous)

Arenite with Iron Oxide matrix

Chalcedony (Agate/Carnelian variant)

Silicon Dioxide (SiO2)

Iron-rich conglomerate or breccia (tentative)

Poorly sorted lithic conglomerate/breccia, with iron-oxide staining; exact composition cannot be determined from the photo

Quartz vein in weathered host rock

Quartz (SiO₂), likely in a weathered metamorphic or igneous matrix

Sandstone (Ferruginous)

Arenite (Fe2O3 rich)

Sandstone (with potential fossil inclusions)

Clastic sedimentary rock (primarily SiO2)

River Pebble (Quartz/Jasper)

Silicon Dioxide (SiO2)

Chalcedony (Common Agate)

Cryptocrystalline Quartz (SiO2)

Pyrite (likely)

Pyrite, FeS₂

Ammonite Fossil (Iridiscent)

Ammonoidea (subclass)

Red jasper in gray host rock (likely hematite-stained quartzite or rhyolite)

Jasper: microcrystalline quartz (SiO₂), with iron-oxide coloration; exact host uncertain from image

Gneiss (specifically Granitic Gneiss)

Gneissic Metamorphic Rock

Rounded beige river pebble, likely quartz-rich sandstone

Quartz-rich sandstone (tentative; exact identification requires testing)

Unidentified light-colored rock or mineral specimen

Indeterminate; possibly weathered calcite-rich material, limestone, or pale quartz-bearing rock

Weathered sandstone or graywacke fragment

Clastic sedimentary rock, likely quartz–feldspar sandstone (exact identification requires testing)

Fossiliferous Limestone Pebble

Biogenic Sedimentary Rock (CaCO3)

Fossil shell fragment in sedimentary rock

Indeterminate marine mollusk shell; likely a bivalve or gastropod fossil

Weathered brown pebble, possibly basalt or iron-rich chert

Provisional identification: fine-grained basalt (plagioclase–pyroxene), potentially coated by iron oxides; exact identification requires testing

Dark gray shale or slate-like rock

Fine-grained, clay-rich mudrock; exact identification is uncertain from the photo

Red-brown pebble, possibly iron-stained sandstone

Indeterminate from the image; likely iron-oxide-stained quartz-rich rock

Mica-rich metamorphic rock (likely mica schist)

Mica schist, composed mainly of muscovite and/or biotite with quartz and possibly feldspar

Quartz-bearing dark rock, possibly hornfels or basalt

Probable quartz–feldspar rock; exact identification requires testing

Weathered brown stone, possibly chert or iron-stained limestone

Uncertain; likely microcrystalline quartz (SiO₂) chert or calcitic limestone (CaCO₃)

Rounded river cobble, likely weathered sandstone or quartzite

Indeterminate clastic silicate rock; possibly quartz-rich sandstone (SiO₂-dominant)

Chalcedony (Jasper/Agate mix)

Quartz (microcrystalline SiO2)

Quartz Crystal Cluster

Silicon Dioxide (SiO2)

Iron-stained weathered stone (tentative)

Undetermined; possibly weathered iron-rich basalt or concretion

Sandstone (likely Arkose)

Arenite (composed mainly of SiO2 with Feldspar)

Fragmented Sedimentary Pebble

Clastic Sedimentary Specimen

Gravel

Unconsolidated aggregate of mixed rock and mineral fragments

Weathered brown rock, likely sandstone or iron-rich sedimentary stone

Indeterminate siliciclastic rock; likely quartz-rich sandstone with iron-oxide cement

Feldspar-rich granite or granitic gneiss

Granite; mainly quartz (SiO₂), feldspar, and mica

Foliated metamorphic rock, likely gneiss or mica schist

Quartz–feldspar–mica metamorphic rock; exact identification is uncertain from the photograph

Weathered sedimentary rock, likely sandstone

Quartz-rich sandstone (tentative identification)

Weathered rock fragment (likely granite or quartz-rich sandstone)

Uncertain; possible granitic fragment containing quartz and feldspar

Weathered Sandstone with Algae Growth

Arenite

Weathered limestone or calcareous sandstone

Calcitic carbonate rock, likely limestone (CaCO₃), possibly slightly dolomitic

Pebble (likely Siltstone or fine-grained Sandstone)

Sedimentary Clastic Rock

Sandstone (with minor weathering/pitting)

Clastic Sedimentary Rock (composed mostly of SiO2)

Sandstone (likely Greywacke or Lithic Sandstone)

Arenite / Wacke

Weathered iron-rich rock (likely ironstone)

Ferruginous ironstone, composed chiefly of iron oxides/hydroxides such as goethite (FeO(OH)) and hematite (Fe₂O₃)

Likely biotite-bearing schist

Mica schist, probably biotite-rich; exact identification is uncertain from the photo