Mineral (Specifically A Mineraloid)

Gneiss (specifically a Banded Gneiss pebble)

Gneiss (High-grade Regional Metamorphic Rock)

Pegmatitic Granite

Granite with Orthoclase Feldspar and Quartz (SiO2, KAlSi3O8)

Gneiss (specifically Banded Gneiss)

Gneiss

Leopard Skin Jasper

Chalcedony (cryptocrystalline Quartz)

Specular Hematite (Specularite)

Iron Oxide (Fe2O3)

Snowflake Obsidian

Volcanic Glass with Spherulite Inclusions (70-75% SiO2)

Chert (specifically Flint)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Quartz Crystal (specifically a small Clear Quartz point)

Silicon Dioxide (SiO2)

Gneiss (specifically a Granitic Gneiss specimen)

Gneiss (high-grade metamorphic rock primarily composed of Quartz, Feldspar, and Biotite/Amphibole)

Pumice (specifically a water-worn, weathered variety)

Vesicular volcanic glass

Yellow Aventurine (specifically a carved crescent moon)

Silicon Dioxide (SiO2) with inclusions

Chert (specifically a nodule with Chalcendony/Agate banding)

Microcrystalline Quartz (SiO2)

Quartzite (specifically a river-worn pebble)

Quartzite (primarily SiO2)

Gneiss (specifically a granitic gneiss cobble)

Gneiss (high-grade regional metamorphic rock)

Chert (specifically a fragment with Desert Varnish)

Microcrystalline quartz (SiO2)

Agate (specifically a Thunderegg/Agate Nodule)

Cryptocrystalline Quartz (SiO2)

Gneiss (specifically a Banded Gneiss cobble)

Gneiss (composed mainly of Quartz, Feldspar, and Biotite/Amphibole)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Blue Lace Agate (Geode/Druzy variant)

Chalcedony (SiO2) with Quartz druzy

Milky Quartz

Silicon Dioxide (SiO₂)

Milky Quartz

Silicon Dioxide (SiO2)

Basalt (Greenstone)

Amygdaloidal Basalt / Chloritized Basalt

Chert (specifically Flint or Jasper variant)

Microcrystalline quartz (SiO2)

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Dalmatian Stone

Dalmatian Jasper (Aplitic Perthite)

Banded Agate (specifically Carnelian Agate color)

Silicon Dioxide (SiO2) - variety of Chalcedony

Serpentine

Serpentinite (group of minerals based on (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4)

Bloodstone

Heliotrope (a variety of Chalcedony, SiO₂ with inclusions)

Moss Agate

Silicon Dioxide (SiO2) with inclusions of hornblende, chlorite, or manganese/iron oxides

Rutilated Quartz

Quartz (SiO2) with Rutile (TiO2) inclusions

Agate

Silicon Dioxide (SiO2)

Sandstone Concretion

Moqui Marble / Ironstone Concretion (Iron oxide-cemented sandstone)

Chert (Tripolitic Chert / Flint Nodules)

Microcrystalline Quartz (SiO2)

Hypersthene

Hypersthene ((Mg,Fe)SiO₃)

Picture Jasper

Silicon Dioxide (SiO2) - Opaque Impure Chalcedony

Limestone (specifically Travertine or Tufa)

Calcium Carbonate (CaCO3)

Obsidian

Obsidian (volcanic glass), primarily SiO2 (silicon dioxide)

Goldstone (Brown)

Aventurine glass

Chert (and/or River Pebble)

Microcrystalline quartz (SiO2)

Blue Sapphire

Corundum (Al2O3 with iron and titanium trace elements)

African Turquoise (Jasper)

Quartz (SiO2) with impurities (Epidote/Amphibole)

Banded Gneiss (River Rock/Pebble)

Gneiss (specifically a banded variety often found as a river rock)