Not A Rock Or Mineral

Quartz (Smoky/Milky Variety)

Silicon Dioxide (SiO2)

Banded Agate

Cryptocrystalline Quartz (SiO2)

Eye Agate

Silicon Dioxide (SiO2) - Banded Chalcedony

Bull Quartz

Quartz (Silicon Dioxide - SiO2)

Vesicular Basalt with Amygdules

Amygdaloidal Basalt

Granitic Gneiss

Gneiss (containing Potassium Feldspar and Quartz)

Jasper (brecciated or orbicular variety)

Silicon dioxide (SiO2) with iron oxide inclusions

Granite

Intrusive Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)

Serpentinite

Serpentinite (composed primarily of Serpentine group minerals, e.g., Antigorite, Lizardite, Chrysotile)

Greenstone / Serpentinite

Serpentinite (composed primarily of minerals from the serpentine group Mg3Si2O5(OH)4)

Pink Granite

Phaneritic intrusive igneous rock (K-feldspar rich)

Yellow Chert (Jasper)

Microcrystalline Quartz (SiO2)

Schist

Mica Schist

Milky Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Gneiss

Gneiss (High-grade Metamorphic Rock)

Prehnite on Basalt

Prehnite - Ca2Al(AlSi3O10)(OH)2

Sandstone

Sandstone (Clastic Sedimentary Rock)

Turquoise

Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]

Banded Agate (specifically Sardonyx Agate)

Silicon Dioxide (SiO2) - Chalcedony variety

Carnelian

Carnelian (Chalcedony / SiO2)

Quartz / Quartzite

Silicon Dioxide (SiO2)

Asphalt (Bituminous Concrete)

Bituminous Concrete / Pavement

Orthoceras Fossil in Limestone

Orthoceras (extinct genus of cephalopods), mineralized as Calcite (CaCO3) in Fossiliferous Limestone

Prehnite

Prehnite Ca2Al2Si3O10(OH)2

Basalt with Amygdules

Amygdaloidal Basalt

Chevron Amethyst

Silicon Dioxide (SiO2) with iron impurities

Gneiss

High-grade regional metamorphic rock (Foliated)

Foliated Gneiss (River-Worn Pebble)

Gneiss (High-grade Regional Metamorphic Rock)

Sandstone

Clastic sedimentary rock (primarily SiO2)

Granite

Granite (Phaneritic intrusive igneous rock)

Basalt

Basalt (Aphanitic Mafic Igneous Rock)

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Amethyst

Amethyst (Silicon Dioxide, SiO2)

Granite

Granite (Felsic Plutonic Rock)

Obsidian

Volcanic glass (high silica volcanic rock)

Serpentine (variety: Serpentine Rock)

Antigorite, Lizardite, or Chrysotile; formula generally (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Drupa Quartz (Sparkly Drusy Quartz on Matrix)

Crystalline Silicon Dioxide (SiO2) on host rock

Clear Quartz

Silicon Dioxide (SiO2)

Milky Quartz/Clear Quartz Cluster

Silicon Dioxide (SiO2)

Granodiorite

Granodiorite (phaneritic intrusive igneous rock)

Sandstone with Ironstone Concretion

Arenite with Hematite/Goethite nodules (Fe2O3 / FeO(OH))