Sedimentary Rock (Possibly Composed Of Various Minerals)

Sandstone (likely Quartzose Sandstone)

Arenite (composed primarily of SiO2)

Quartz (Milky/Clear variety)

Silicon Dioxide (SiO2)

Granite

Felsic Intrusive Igneous Rock

Sandstone

Arenite (composed primarily of SiO2)

Gneiss (specifically a Granitic Gneiss specimen)

Gneiss (high-grade metamorphic rock primarily composed of Quartz, Feldspar, and Biotite/Amphibole)

Sandstone (with garnet granules)

Clastic sedimentary rock (primarily SiO2 with Fe3Al2(SiO4)3 inclusions)

Diorite (Spotted or Dalmatian Stone effect)

Diorite (Intermediate Plutonic Rock)

Sandstone (Stream Pebble)

Arenite (primarily SiO2)

Granite

Granite (Felsic Plutonic Rock)

Sandstone (specifically Flagstone)

Arenite (primarily composed of SiO2)

Sandstone (Quartzose Sandstone)

Arenite

Asphalt (Bituminous Pavement)

Bituminous mix (Aggregates with Bitumen binder)

Fossilized Gastropod (Snail)

Class Gastropoda (internal mold or 'steinkern')

Sandstone (Quartzose Sandstone)

Arenite (composed primarily of SiO2)

Red Sandstone (Arkose)

Clastic Sedimentary Rock (Lithic Arkose)

Quartz (likely Jasper or Chert variety)

Quartz (SiO₂)

Marble

Recrystallized Calcite (CaCO3)

River Cobble (Gneiss/Migmatite)

Gneissic Metamorphic Rock (composed mainly of Quartz, Feldspar, and Biotite)

Sandstone

Arenite (composed primarily of SiO2)

Sandstone (with Iron Staining)

Clastic sedimentary rock (primarily SiO2 with Fe2O3 oxides)

Sandstone (with prominent jointing/fractures)

Arenite (composed primarily of SiO2)

River Rock

Sedimentary Rock (various compositions)

Quartz

SiO₂ (Silicon Dioxide)

Sandstone (with potential trace fossils)

Clastic sedimentary rock (primarily SiO2)

Sandstone (specifically Picture Sandstone or Wonderstone)

Arenite (composed primarily of SiO2)

Sandstone (likely Arkose or Quartz Sandstone)

Arenite (SiO2 + varied clasts)

Oolitic Limestone

Oolite (Sedimentary rock composed of CaCO3)

Dalmatian Jasper (Dalmatian Stone)

Dalmatian Stone (primarily Feldspar, Quartz, and Arfvedsonite/Tourmaline)

Dendrite (Manganese Oxide Dendrites)

Psilomelane or Pyrolusite on Matrix (typically MnO2)

Sandstone (Pebble)

Arenite / Clastic Sedimentary Rock

Sandstone

Arenite (Siliclastic sedimentary rock)

Biotite (Black Mica)

Biotite - K(Mg,Fe)3AlSi3O10(F,OH)2

Diorite (Salt and Pepper Rock)

Phaneritic Plutonic Diorite; chemical composition roughly 52-63% silica (SiO2)

Fluorite with Rhodochrosite

Fluorite (CaF2) and Rhodochrosite (MnCO3)

Marble (White)

Metamorphosed Limestone (mainly CaCO3)

Dalmatian Jasper (or Dalmatian Stone)

Dalmatian Stone (A peralkaline felsite composed of feldspar, quartz, and sodic amphibole)

Metal Alloy (Likely Pewter or Sterling Silver)

Not a natural geological specimen; composed of refined metals. If pewter, it's a tin-based alloy. If sterling silver, it's 92.5% silver and 7.5% other metals (usually copper).

Sandstone (clastic)

Clastic Sedimentary Rock (primarily composed of SiO2)

Sandstone (Flagstone)

Arenite (composed primarily of SiO2)

Sandstone (Gneissic or Banded)

Clastic Sedimentary Rock (composed predominantly of SiO2)

Granite

Granite (Felsic Plutonic Rock)

Clear Quartz Crystal

Quartz (Silicon Dioxide, SiO2)