Metamorphic Rock (Specifically A Rock Composed Of Minerals)

Sandstone

Arenite (composed primarily of SiO2)

Sandstone

Clastic Sedimentary Rock (primarily SiO2)

Unakite

Epidotized Granite

Sandstone

Sandstone (Clastic Sedimentary Rock)

Granitic Gneiss

Gneiss (High-grade regional metamorphic rock)

Black Marble

Recrystallized Carbonate Rock (CaCO3)

Sandstone

Arenite (Siliclastic sedimentary rock)

Thunderegg (specifically a Jasper/Agate-filled Geode nodule)

Silicon Dioxide (SiO2) within Rhyolitic Matrix

Almandine Garnet in Schist Matrix

Almandine - Fe3Al2(SiO4)3

Sandstone

Arenite (often composed of Quartz, SiO2)

Banded Gneiss

Gneiss (High-grade Metamorphic Rock)

Amethyst (Chevron or Banded variety)

Silicon Dioxide with Iron impurities (SiO2)

Blue Lace Agate

Silicon dioxide (SiO2) - Chalcedony variety

Chalcedony in Matrix

Silicon Dioxide (SiO2)

Metagabbro / Epidote Gneiss

Epidote bearing Hornblende Gneiss

Slate

Foliated Metamorphic Rock (composed mainly of Quartz, Illite, and Chlorite)

Garnet Schist

Almandine Garnet Schist

Sandstone

Arenite (composed primarily of SiO2)

Milky Quartz with Iron Staining

Silicon Dioxide (SiO2)

Sandstone (with man-made markings)

Arenite (composed primarily of Quartz, SiO2)

Granite

Granite (Phaneritic igneous rock)

Unakite (Epidotized Granite)

Epidote-Feldspar-Quartz Rock

Basalt (Polished Pebble)

Basalt (Mafic volcanic rock)

Sandstone

Sandstone (arenite is a more specific geological term for a clean sandstone, while wacke refers to a dirty sandstone with significant matrix)

Pink Granite

Granite (Phaneritic igneous rock)

Quartz (Milk Quartz / Massive Quartz)

Silicon Dioxide (SiO2)

Sandstone (likely Arkose)

Arenite (composed mainly of SiO2 with Feldspar)

Sandstone (Micaceous)

Arenite (composed primarily of SiO2)

Quartz Mica Schist

Mica-Quartz Schist (Chemical: SiO2 + KAl2(AlSi3O10)(OH)2)

Shale

Fissile mudrock (composed of clay-sized particles and detrital grains)

Dendritic Agate (specifically Orange/Tumbled)

Silicon Dioxide (SiO2) with Oxide Inclusions

Sandstone (Stream Pebble)

Arenite (primarily SiO2)

Milky Quartz (with trace inclusions)

Silicon Dioxide (SiO2)

Moonstone (Green Moonstone / Garnierite)

Potassium Aluminum Silicate (KAlSi3O8) with inclusions of Garnierite

Sandstone

Arenite (composed primarily of SiO2)

Feldspar-rich Granite (Pink Granite)

Phaneritic Felsic Igneous Rock

Sandstone (Pebble)

Arenite / Clastic Sedimentary Rock

Banded Gneiss

Gneiss (Metamorphic high-grade rock)

Blue Quartzite

Quartzite (primarily SiO2 with inclusions like Dumortierite or Magnesio-riebeckite)

Sandstone (specifically an Iron-Concretion)

Arenite with Iron Oxide (Limonite/Goethite) cementation

Sandstone (with garnet granules)

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

Biotite Gneiss

Gneiss (complex mixture including Biotite K(Mg,Fe)3AlSi3O10(F,OH)2 and Quartz/Feldspar)