This Is Not A Rock Or Mineral

Snowflake Obsidian

Vitreous Volcanic Rock (Amorphous Silicate), SiO2

Picture Jasper

Silicified sedimentary or volcanic rock (primarily SiO2)

Diorite

Diorite (Intermediate intrusive igneous rock)

Gneiss

Gneiss (High-grade regional metamorphic rock)

Pink Opal

Hydrated Amorphous Silica (SiO2·nH2O)

Serpentinite

Serpentinite (composed primarily of Serpentine minerals: Mg3Si2O5(OH)4)

Native Gold Nugget

Native Gold (Au)

Bumble Bee Jasper

Calcite-bearing Volcanic Tuff (not a true Jasper)

Amygdaloidal Basalt

Amygdaloidal Basalt (extrusive volcanic rock with secondary mineral infilling)

Quartz (Fieldstone/Pebble)

Silicon Dioxide (SiO2)

Granite

Granite (Phaneritic Quartz-Feldspar intrusive rock)

Epidote

Epidote Group (e.g., Clinozoisite, Epidote, Piemontite), Epidote formula: Ca2(Al,Fe)3(SiO4)3(OH)

Quartzite with Hematite

Metamorphosed Quartz Sandstone (SiO2 with Fe2O3 inclusions)

Pink Sapphire

Corundum (Al2O3 with trace Chromium and Iron)

Quartzite

Quartzite (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Dendritic Agate (or Dendritic Opal)

SiO2 (for Agate), SiO2·nH2O (for Opal)

Basalt with Plagioclase Phenocrysts

Porphyritic Basalt (primarily SiO2, MgO, FeO, and CaO)

Porphyritic Basalt

Amygdaloidal Porphyritic Basalt

Porphyritic Andesite

Andesite

Slate

Foliated Metamorphic Rock (composed primarily of silica and alumina with iron and magnesium)

Granite (specifically Pink or Red Granite)

Phaneritic Felsic Igneous Rock (Granite)

Chert (Nodular)

Chert (SiO2 - Microcrystalline Quartz)

Petrified Wood

Silicified Wood (primarily SiO2)

Gneiss (with Quartz and Biotite Mica)

Gneiss

Almandine Garnet

Iron aluminum silicate (Fe3Al2(SiO4)3)

Gastropod Steinkern (Fossil Snail Internal Mold)

Class Gastropoda (Internal Mold)

Sunstone (variety of Feldspar)

Oligoclase Sunstone, Plagioclase Feldspar (Na,Ca)Al(Si,Al)Si2O8

Granite (Micro-specimen)

Plutonic Igneous Rock (primarily Quartz, Feldspar, and Mica)

Pink Granite

Granite (Phaneritic felsic intrusive igneous rock)

Quartz

Quartz (SiO₂)

Snowflake Obsidian

Volcanic glass containing Spherulite inclusions (primarily Cristobalite, SiO2)

Pink Granite

Phaneritic Felsic Igneous Rock (Granite)

Jasper-Agate Breccia

Silicon Dioxide (SiO2) with iron oxide inclusions

Greenschist (Chlorite Schist)

Greenschist (containing chlorite, actinolite, and epidote)

Banded Agate (specifically Carnelian Agate slice)

Chalcedony (cryptocrystalline variety of Quartz), SiO2

Bumblebee Jasper

Calcite-bearing Volcanic Tuff containing Sulfur and Arsenic (Orpiment/Realgar)

Puddingstone

Conglomerate (Indurated)

Clay (as a rock-forming material)

Clay minerals (e.g., Kaolinite group, Smectite group, Illite group, Chlorite group)

Liesegang Ring Siltstone

Siltstone with iron oxide Liesegang bands