Rock (Likely Sedimentary)

Micaceous schist (likely biotite schist)

Schist dominated by biotite mica, quartz, and feldspar

Biotite granite (weathered granitic rock)

Granite; chiefly quartz (SiO₂), feldspar, and biotite mica

Likely vertebra fossil or bone fragment

Indeterminate fossilized vertebra; mineralized hydroxyapatite, commonly Ca₅(PO₄)₃(OH)

Calcite

Calcite (calcium carbonate, CaCO₃), likely a massive crystalline specimen

Rounded river cobble, likely weathered sandstone or quartz-rich metasandstone

Indeterminate sandstone; commonly quartz (SiO₂) with feldspar, lithic grains, and iron-oxide cement

Quartz Crystal Cluster on Matrix

Silicon Dioxide (SiO2)

Granite Pebble

Phaneritic Felsic Igneous Rock

Quartz (likely Herkimer Diamond style)

Silicon Dioxide (SiO2)

Weathered carbonate rock, possibly fossiliferous limestone

Calcite-rich limestone (CaCO₃), tentative identification

Weathered basalt or iron-rich volcanic rock

Mafic volcanic rock, likely basalt; exact identification requires testing

Gneiss (with Quartz-Feldspar vein)

Gneiss (high-grade metamorphic rock) containing Quartz (SiO2) and Feldspar (KAlSi3O8 – NaAlSi3O8 – CaAl2Si2O8)

Sandstone (with vugs or solution cavities)

Arenite (primarily Quartz and Feldspar with CaCO3 or SiO2 cement)

Unidentified River Rock or Mudstone

N/A (Generic rock fragment)

Banded Chert (likely Flint or Jasper variety)

Silicon Dioxide (SiO2)

Iron-rich concretion or weathered ironstone

Goethite–hematite limonite aggregate; commonly described as limonite or ironstone

Sandstone (likely Graywacke or Arkose variant)

Clastic Sedimentary Rock (SiO2 with assorted lithic fragments)

Iron-rich quartzite or ironstone fragment

Quartzite dominated by quartz (SiO₂), with iron oxides such as hematite/goethite

Sandstone (likely Graywacke or Lithic Sandstone)

Arenite / Wacke (SiO2 based with lithic fragments)

Petrified Wood

Silicified Wood (primarily SiO2)

Quartz-rich rock, possibly milky quartz or quartzite fragment

Quartz (SiO₂), potentially quartzite if metamorphic

Chert / Flint Pebble with Fossil Cavity

Silicon Dioxide (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Weathered chert or jasper nodule

Microcrystalline quartz (SiO₂), likely chalcedony/jasper with iron-oxide staining

Pink Gneiss / Pink Granite Gneiss

Felsic Gneiss (dominated by Orthoclase Feldspar and Quartz)

Ironstone (likely Limonite or Goethite)

Ferruginous sedimentary rock (FeO(OH)·nH2O)

Chert (Yellow Jasper/Flint)

Microcrystalline Quartz (SiO2)

Wishing Stone (Basalt/Greywacke with Quartz Vein)

Basalt or Siltstone with SiO2 (Quartz) hydrothermal intrusion

Granite

Granite (Phaneritic Igneous Rock)

Sandstone with Ironstone Banding

Clastic Sandstone (composed of Quartz with Hematite/Limonite bonding)

Sandstone (likely Quartzose Sandstone)

Arenite

Rounded yellow-brown pebble

Likely iron-stained sandstone or quartz-rich river cobble

Jasper

Silicon dioxide (SiO2)

Weathered quartzite cobble

Quartzite, predominantly crystalline SiO₂

Banded Sandstone (Quartzite-rich)

Clastic Sedimentary Rock (SiO2 with Iron Oxide impurities)

Likely weathered limestone or calcite-rich stone

Limestone, primarily calcium carbonate (CaCO₃), possibly calcite

Fossil Shell (Bivalve)

Class Bivalvia (Likely a member of the Ostreidae or Gryphaeidae family), CaCO3

River Cobble (Quartzite or Weathered Sandstone)

Arenite / Metasandstone (SiO2)

Weathered sandstone or iron-stained sedimentary pebble

Quartz-rich sandstone; exact identification requires a fresh surface and tests

Weathered sandstone or iron-rich mudstone fragment

Clastic sedimentary rock, likely quartz–feldspar sandstone with iron-oxide cement

Quartz Pebble (Chalcedony/Agate variety)

Silicon Dioxide (SiO2)

Likely chlorite-bearing schist (possibly greenschist)

Chlorite–quartz–mica schist; commonly contains muscovite/biotite and feldspar

Weathered iron-rich rock, possibly limonite-bearing sandstone or laterite

Limonite/goethite-rich ferruginous rock; exact identification requires testing