Not A Rock Or Mineral (Anthropogenic Material)

Sandstone

Arenite (SiO2 primarily)

Basaltic Tuff / Volcanic Breccia

Pyroclastic Breccia / Lithic Tuff

Fossil Snail

Gastropoda fossil

Sandstone (with Concretion)

Arenite / Quartzose Sandstone

Polished dark stone, possibly black tourmaline or a dark pebble

Undetermined; image lacks detail for reliable identification

Blue-green copper mineral-bearing rock, likely chrysocolla with malachite

Chrysocolla (hydrated copper aluminosilicate, approximately (Cu,Al)₂H₂Si₂O₅(OH)₄·nH₂O) with malachite (Cu₂CO₃(OH)₂), possibly in altered host rock

Sandstone (likely Siltstone or fine-grained Sandstone)

Sedimentary Rock (Clastic)

Banded metamorphic rock, likely gneiss or amphibolite

Composition uncertain; probable quartz–feldspar–amphibole assemblage

Sandstone

Arenite (Sedimentary Rock)

Asphalt (Bituminous Rock)

Natural bitumen or Bituminous limestone/sandstone

Weathered gray stone, possibly basalt or granitic rock

Indeterminate fine- to medium-grained silicate rock; possible basalt, diabase, or weathered granite

Sandstone (Quartzose)

Arenite (composed primarily of SiO2)

Sandstone

Arenite

Sandstone

Arenite (Sedimentary rock composed of sand-sized grains)

Granite Cobble / Gneiss (River Rock)

Granitic Gneiss / Felsic Igneous Rock

Sandstone

Arenite (SiO2 dominant)

Rough amethyst-bearing quartz specimens

Quartz, SiO₂; purple coloration from trace iron and irradiation

Tumbled quartz-rich pebble

Likely milky quartz with a dark mafic inclusion or attached basalt; exact identification requires testing

Sandstone (Red)

Arenite (composed primarily of SiO2)

Sandstone

Sedimentary Rock (Quartz arenite)

Red heart-shaped glass bead in a wire-wrapped jewelry charm

Likely colored glass (amorphous silica-based material); the image does not show an identifiable geological specimen

Sandstone (Ferruginous)

Arenite (primarily SiO2 with iron oxide Fe2O3 cement)

Granite-like rock

Felsic intrusive igneous rock, probably granitic or granodioritic

Red Sandstone

Sedimentary Clastic Rock (Quartz Arenite)

Mixed rough mineral specimens, likely quartz-bearing rocks

Probable quartz (SiO₂), with possible feldspar, iron oxides, and altered host rock

Green serpentine (likely serpentine-rich stone)

Serpentine-group minerals, chiefly antigorite, lizardite, or chrysotile; composition approximately Mg₃Si₂O₅(OH)₄

Small rounded pebble, possibly quartz-rich stone

Indeterminate; likely quartz/quartzite or a weathered feldspathic pebble

Granite

Intrusive Igneous Rock

Weathered mica-rich schist

Muscovite–biotite schist, possibly quartz-bearing

Sandstone

Sedimentary Rock (Quartz arenite / Lithic sandstone)

Sandstone

Sandstone (Quartz-rich sedimentary rock)

Small water-worn pebble, likely quartz-rich

Rock fragment of uncertain composition; possibly quartzite or chert

Sandstone

Sandstone (composed predominantly of Quartz, SiO2)

Sandstone

Sedimentary Rock (Quartzose Sandstone)

Rock Fragment with Calcite/Quartz Vein

Polymictic Rock Fragment (SiO2 / CaCO3)

Sandstone

Arenite (SiO2 principal)

Sandstone

Arenite (SiO2 principal)

Geode or Concretion

Silica-filled nodule (likely SiO2)

Small weathered mineral/rock fragment

Unidentified; likely quartz-rich material, possibly quartzite or feldspar-bearing rock

Fossil Snail

Gastropoda (fossilized)

Possible fossilized shell or coral fragment

Indeterminate biogenic carbonate, likely calcite (CaCO₃)

Sandstone

Arenite