Sedimentary Rock (Specifically A Chemical Sedimentary Rock, Or A Chert If Considered Purely Mineral Aggregate)

Dyed Agate Slice

Silicon Dioxide (SiO2) with artificial colorants

Picture Jasper

Silicified sedimentary or volcanic rock (primarily SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Quartz Druze on Matrix

Silicon Dioxide (SiO2)

Sandstone (Ferruginous)

Clastic sedimentary rock (primarily SiO2 with Fe2O3 cement)

Clear Quartz Crystal

Quartz (Silicon Dioxide, SiO2)

Red Jasper

Jasper (Silicon Dioxide, SiO2 with Fe2O3 inclusions)

Halite (Rock Salt)

Halite; NaCl (Sodium Chloride)

Red Sandstone

Arenite (primarily Quartz SiO2 with Hematite Fe2O3 cement)

Red Shale

Lutite (primarily composed of Hydrous Aluminum Silicates with Hematite staining)

Petrified Wood

Silicified Wood (primarily SiO2)

Garnet Schist

Almandine Garnet-Mica Schist (X₃Y₂(SiO₄)₃)

Red Sandstone

Arenic rock (composed mainly of SiO2 with Fe2O3)

Dendritic Agate (River Pebble)

Silicon Dioxide (SiO2) with Manganese or Iron oxide inclusions

Chalcedony (Botryoidal/Agate nodule)

Microcrystalline Quartz (SiO2)

Banded Agate (with Quartz Geode Center)

Silicon Dioxide (SiO2)

Sandstone

Arenite

Gneiss (Metamorphic Rock)

Gneiss

Schist

N/A (a rock type, not a mineral formula)

Sandstone

Arenite (composed primarily of SiO2)

Red Jasper

Red Jasper (SiO2 with Fe2O3 impurities)

Banded Sandstone

Arenite (composed primarily of Quartz: SiO2)

Shale with Pyrite

Clastic sedimentary rock containing Iron Disulfide (FeS2)

Fossilized Coral

Scleractinia (fossil order), primarily Calcium Carbonate (CaCO3)

Limonite (Iron Stone)

Limonite (Hydrated Iron Oxide) - FeO(OH)·nH2O

Bumblebee Jasper

Fossiliferous Calcite containing Orpiment and Realgar

Marble

Metamorphosed Limestone (main mineral: Calcite, CaCO3)

White Agate (Chalcedony)

Silicon Dioxide (SiO2)

Almandine Garnet in Schist Matrix

Almandine - Fe3Al2(SiO4)3

Septarian Nodule Segment (Turtle Stone)

Septarian Concretion (CaCO3 with Siderite or Calcite infill)

Blue Quartz

Quartz (SiO2) with inclusions

Chert (often called Flint when dark or found in chalk)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Red Sandstone

Arenite (with Iron Oxide / Hematite cementation)

Petrified Wood

Silicified Wood (primarily SiO₂ / Silicon Dioxide)

Blue Chalcedony

Microcrystalline Quartz (SiO2)

Calamites (Fossilized Horsetail)

Calamites suckowii (Family: Calamitaceae)

Petrified Wood

Silicified Wood (primarily SiO2)

Jasper-Agate Breccia

Silicon Dioxide (SiO2) with iron oxide inclusions

Quartz (with iron oxide staining)

Silicon Dioxide (SiO2)

Red Sandstone

Arenite (primarily Quartz with Hematite cement)

Sandstone (Ferruginous)

Arenite (composed primarily of SiO2 with Fe2O3 cement)

Red Sandstone

Clastic sedimentary rock (primarily SiO2 with Fe2O3)