Not A Rock Or Mineral (Anthropogenic Material)

Granite

Granite (a broadly defined plutonic igneous rock, often more specifically classified as quartz monzonite or granodiorite based on precise mineral percentages)

Sandstone

Arenite (composed primarily of SiO2)

River Cobble (Quartzite with Iron Staining)

Metamorphic Quartzite (SiO2 with Fe2O3 inclusions)

Diorite

Diorite (Intermediate intrusive igneous rock)

Petrified Wood

Silicified Wood (SiO2)

Conglomerate

Conglomerate (a clastic sedimentary rock)

Sea Glass

Amorphous Silica (SiO2) with various additives

Quartzite

Quartzite (primarily SiO2)

Ferruginous Breccia

Breccia with Iron-rich (Hematite/Goethite) Matrix

Blue Sphalerite (likely dyed or treated Druzy Quartz/Agate)

Zinc Sulfide (ZnS) or Silicon Dioxide (SiO2) with trade-name enhancement

Epidote in Quartz

Quartz with Epidote inclusions (SiO2 with Ca2(Al,Fe)3(SiO4)3(OH) inclusions)

Riverstone Quartzite

Quartzite (primarily SiO2)

Granite

Granite (felsic intrusive igneous rock)

Chert (Arrowhead or Projectile Point)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Nodule)

Silicon Dioxide (SiO2)

Conglomerate

Conglomerate (Sedimentary rock containing rounded clasts)

Chert (Jasper/Flint variation)

Chert (SiO2)

Mica Schist with Garnet

Garnetiferous Mica Schist

Sandstone (specifically Arkose or Ferruginous Sandstone)

Sandstone (SiO2 with iron oxide inclusions)

Black Obsidian

Volcanic Glass (predominantly SiO2, Silicon Dioxide)

Serpentinite

Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4

Limestone (Grey and White specimens)

Calcium Carbonate (CaCO3)

Limestone

Calcium Carbonate (CaCO3)

Gneiss

Gneiss (Metamorphic rock of variable composition, typically SiO2 rich)

Phyllite

Phyllite (Foliated metamorphic rock)

Sandstone

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

Chert Nodule (Flint)

Chert (Cryptocrystalline Silica - SiO2)

Scoria

Scoria (a vesicular basalt or andesite)

Quartzite Cobble

Quartzite (primarily SiO2)

Agate (specifically, multi-colored or pastel-dyed agate)

Silicon dioxide (SiO2) - specifically, a cryptocrystalline variety of quartz known as Chalcedony, with banding classified as Agate. (If it were Fluorite, the chemical formula would be Calcium Fluoride - CaF2).

Granite Cobble

Granite (Phaneritic igneous rock composed of Quartz, Feldspar, and Mica)

White Marble

Recrystallized Calcite (CaCO3) / Marble

Basalt

Basalt (Aphanitic mafic volcanic rock)

Agate

Agate (Cryptocrystalline Variety of Quartz, SiO2)

Granite

Granite (a felsic intrusive igneous rock)

Schist

Mica Schist (Medium-grade metamorphic rock)

Quartzite Pebble

Quartzite (SiO2)

Ferruginous Slag (Iron Smelting Byproduct)

Fused Silicate Scoria (Amorphous mixture of FeO, SiO2, and CaO)

River Stone (River Pebbles)

Alluvial Deposit (typically Quartzite, Sandstone, or Granite clasts)

Chert (Chalcedony/Flint)

Silicon Dioxide (SiO2)

Basalt

Basalt (Aphanitic Mafic Volcanic Rock)

Brecciated Jasper

Silicon Dioxide (SiO2) with varying mineral inclusions (Iron Oxide, Hematite, Clay)