Not A Rock Or Mineral

Aquamarine and clear quartz

Aquamarine (Be3Al2Si6O18), Quartz (SiO2)

Rough Green QuartzITE / Green Aventurine

Aventurine Quartz (SiO2 + Cr-muscovite inclusions)

Amygdaloidal Basalt

Amygdaloidal Basalt (Host rock) with Quartz or Calcite amygdules

Schist

Mica Schist

Tree Agate

Dendritic Agate (Silicon Dioxide - SiO2)

Amethyst Geode

Silicon Dioxide with trace inclusions of Iron (SiO2)

Banded Agate (Onyx variety)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Carnelian (a variety of Chalcedony)

Cryptocrystalline Quartz (SiO2) with iron oxide inclusions

Gold Nugget

Native Gold (Au)

Sandstone

Clastic Sedimentary Rock (composed mostly of SiO2)

Chert (varietal: Flint/Jasper mix)

Hydrous Silica (SiO2)

Shale

Shale (fine-grained clastic sedimentary rock)

Chert (often called Flint when dark)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Quartz (likely tumbled or naturally water-worn)

Quartz (SiO₂ - Silicon Dioxide)

Blue Chalcedony

Chalcedony (Silicon Dioxide, SiO2)

Conglomerate

Conglomerate (a clastic sedimentary rock)

Gold Ore in Matrix

Native Gold (Au) in Quartz/Host Rock

Yellow Jasper

Silicon Dioxide (SiO2) with iron hydroxides (Goethite/Limonite)

Sandstone (likely Fossilized Wood or Concrete Simulacrum)

Arenite / Silicified Wood / Anthropogenic Concrete

Fancy Jasper (Multicolor Agate/Jasper)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Fulgurite

Fulgurite (Lechatelierite), amorphous SiO2

Basalt

Extrusive Mafic Igneous Rock (composed primarily of plagioclase feldspar and pyroxene)

Banded Gneiss

Gneiss (Metamorphic high-grade rock)

Gneiss (specifically Pink Gneiss)

Gneiss (high-grade regional metamorphic rock)

Basalt with Olivine Phenocrysts

Porphyritic Basalt (Mineral formula of Olivine: (Mg,Fe)2SiO4)

Honey Calcite (Yellow Calcite)

Calcium Carbonate (CaCO3)

Granite

Granite (Felsic Plutonic Rock / SiO2 + Al2O3 + K2O + Na2O + CaO + FeO + MgO)

Concrete

Anthropogenic Sedimentary Rock (Hydrated Calcium Silicate)

Sandstone (likely Graywacke or Lithic Sandstone)

Arenite / Wacke (SiO2 based with lithic fragments)

Oolitic Limestone

Oolite (Sedimentary rock composed of CaCO3)

Amethyst (Pale/Lavender variety)

Silicon Dioxide (SiO2)

Tree Agate

Dendritic Agate (Silicon Dioxide, SiO2)

Rose Quartz

Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese

Smoky Quartz (with possible Feldspar inclusions)

Silicon Dioxide (SiO2)

Red Quartz (Carnelian/Red Jasper Agate)

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Desert Rose (Gypsum Variety)

Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Quartz (Clear / Rock Crystal)

Silicon Dioxide (SiO2)

Schorl (Black Tourmaline) in Pegmatite

Sodium Iron Aluminum Borosilicate (NaFe3Al6(BO3)3Si6O18(OH)4)

Greenstone (Greenstone River Pebble)

Greenschist (metamorphosed mafic igneous rock)

Porphyritic Basalt (Amygdaloidal)

Porphyritic Mafic Volcanic Rock (Amygdaloidal Basalt)

Petrified Wood

Silicified Wood (SiO2)