Rock (Likely Sedimentary)

Sandstone (Sedimentary Rock)

Arenite (SiO2 based)

Likely bituminous coal

Coal, predominantly maceral-rich carbonaceous material (composition varies)

Mixed collection of small rounded pebbles

Unidentified river- or beach-worn lithic clasts; individual rock types cannot be determined confidently from the image

Possible fossil-bearing pebble

Unidentified fine-grained sedimentary rock; the small orange feature may be a fossil or mineral inclusion

Quartz-encrusted Matrix

Silicon Dioxide (SiO2) with Ferruginous Sandstone

Sandstone

Arenite (SiO2 based)

Sandstone (Ferruginous)

Arenite (primarily SiO2 with Iron Oxide cement)

Likely gneiss

Foliated quartz–feldspar gneiss; exact identification requires closer examination

Small rounded pebble or stone

Unidentified lithic pebble; composition cannot be determined from the photograph

Rounded tan pebble

Unidentified fine-grained rock; the image does not show enough detail for a reliable species-level identification.

Weathered, iron-stained rock fragment

Unidentified iron-oxide-stained silicate rock; precise identification is not possible from the image

Sandstone (likely Arkosic)

Clastic Sedimentary Rock (Sandstone)

Conglomerate (possibly breccia/conglomeratic rock)

Polymictic conglomerate; composition and exact classification are uncertain from the image

Weathered gneissic or granitic rock

Quartz–feldspar–biotite gneiss (tentative; possibly weathered granite)

Mixed stream-worn rocks, likely including quartz-rich gravel

Composition indeterminate; visible material may include quartz (SiO₂) and assorted lithic fragments

Weathered sandstone pebble

Quartz-rich sandstone; predominantly SiO₂ grains cemented by silica, calcite, or iron oxides

Weathered river pebble (likely iron-stained rock)

Indeterminate from the image; possibly iron-oxide-stained quartzite or sandstone

Fossil-bearing limestone (probable)

Limestone, chiefly calcite (CaCO₃), with a visible spiral fossil that may be a gastropod

Rounded river pebble, likely quartz-rich sandstone

Quartz-rich sandstone (tentative; exact identification is limited from the image)

Reddish sandstone (probable)

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

Sandstone (Greywacke)

Arenite / Clastic Sedimentary Rock

Quartz with iron staining

Silicon dioxide (SiO2)

Weathered yellow-brown rock fragment

Indeterminate; possibly iron-stained sandstone or weathered limestone

Rounded sandstone cobble

Quartz-rich sandstone (likely), with grains cemented by silica, calcite, or iron oxides

Gastropod Fossil (Snail Steinkern)

Class Gastropoda fossil, composed of Calcium Carbonate (CaCO3)

Agate

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Sandstone (Fossiliferous)

Arenite / Clastic Sedimentary Rock

Ironstone concretion (likely limonite/goethite-rich)

Iron-oxide-cemented sediment, commonly goethite (FeO(OH)) and/or limonite

Unidentified yellow-orange mineral fragment

Possibly iron-stained quartz, calcite, or citrine; identification is uncertain from the image

Chert or silicified limestone (uncertain)

Microcrystalline quartz (SiO₂), possibly calcitic limestone (CaCO₃)

Sandstone

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

Fine-grained sedimentary rock, likely mudstone

Mudstone (clay- and silt-sized siliciclastic sedimentary rock)

Fossil-bearing sedimentary rock, likely with a fossil shell or ammonite cross-section

Fossiliferous limestone or calcareous mudstone; fossil identity is uncertain from the image

Sandstone (Quartzose)

Sandstone (clastic sedimentary rock, primarily SiO2)

Rounded gray stone, likely slate or fine-grained sandstone

Probable slate (low-grade metamorphosed shale) or lithic sandstone; exact identification requires testing

Likely mica-rich schist

Mica schist, composed mainly of muscovite and/or biotite with quartz; exact identification is uncertain from the photo.

Sandstone

Sandstone (clastic sedimentary rock)

Unidentified dark gray rock fragment

Likely fine-grained basalt or andesite; exact identification requires testing

Iron-stained milky quartz vein

Quartz (SiO₂), with reddish iron-oxide staining, likely hematite or goethite

Rounded river pebble (likely fine-grained sandstone or quartzite)

Indeterminate from image; likely quartz-rich sandstone, possibly quartzite

Likely biotite-rich schist

Mica schist, likely biotite-rich; exact minerals cannot be confirmed from the photo

Chalcedony Geode Fragment

Silicon Dioxide (SiO2) - Microcrystalline Quartz