Sedimentary Rock

Ferruginous Sandstone (Ironstone)

Sedimentary rock with high iron oxide content (Fe2O3 / FeO(OH))

Sandstone (with garnet granules)

Clastic sedimentary rock (primarily SiO2 with Fe3Al2(SiO4)3 inclusions)

Chert (varietal known as Jasper or Flint)

Silicon Dioxide (SiO2)

Ferruginous Sandstone (Ironstone)

Clastic Sedimentary Rock (composed of SiO2 with Fe2O3/FeO(OH) cement)

Red Sandstone

Clastic sedimentary rock (primarily SiO2 with Fe2O3 iron oxide staining)

Chert (Flint)

SiO2 (predominantly microcrystalline or cryptocrystalline quartz)

Red Jasper (beads)

Silicon Dioxide (SiO2) with iron inclusions

Chalk

Calcareous Ooze (composed primarily of coccoliths)

Banded Iron Formation (BIF)

Banded Iron Formation

Coal (most likely Bituminous or Anthracite)

Bituminous Coal (Grade of Coal), Anthracite (Grade of Coal)

Cherry Creek Jasper (also known as Red Creek Jasper or Cherry Creek Agate)

Jasper, microcrystalline quartz (SiO₂)

Coal (most likely Bituminous or Anthracite)

Coal (primarily composed of carbon with varying amounts of other elements)

Ocean Jasper (Orbicular Jasper)

Silicon Dioxide (SiO2)

Sandstone

Arenite (general term for sandstone)

Quartzite

Quartzite (primarily composed of SiO O₂)

Chert (or possibly Flint)

SiO2 (Silicon Dioxide)

Jasper, possibly Brecciated Jasper or Ocean Jasper due to patterns and color

Silicon Dioxide (SiO2), a variety of Chalcedony

Red Jasper

Jasper (a cryptocrystalline variety of Quartz, SiO₂)

Banded Iron Formation

Banded Iron Formation (BIF)

Hag Stone

Naturally holed stone (typically sedimentary rock such as flint, limestone, or sandstone)

Chert (or Flint)

Chert (cryptocrystalline quartz), SiO2

Shale with Limonite/Hematite Staining

Argillaceous sedimentary rock with Iron Oxides (FeO(OH)·nH2O / Fe2O3)

Sandstone Concretion

Clastic sedimentary rock (primarily Silica, SiO2, or Calcium Carbonate, CaCO3)

Red Sandstone

Clastic sedimentary rock (primarily Quartz and Feldspar with Iron Oxide cement)

Ironstone (Limonite/Hematite)

Ferruginous Sedimentary Rock (composed largely of Fe2O3 and FeO(OH)·nH2O)

Ironstone Concretion / Hematite Nodules

Ferruginous Sedimentary Rock (primarily Hematite Fe2O3 and Goethite FeO(OH))

River Stone (likely Mudstone or Siltstone)

Lutite (Clastic sedimentary rock composed of clay and silt-sized particles)

Greenstone (Greywacke or Nephrite Jade variant)

Metamorphosed mafic igneous or sedimentary rock (e.g., Actinolite-Chlorite Schist)

Red Sandstone

Clastic Terrigenous Sedimentary Rock (typically Hematitic Quartz Arenite or Arkose)

Travertine

Calcium Carbonate (CaCO3)

Chert (Nodule)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Geode or Concretion

Silica-filled nodule (likely SiO2)

Sandstone (Ferruginous)

Arenite (primarily SiO2 with Fe2O3 cement)

Ferruginous Sandstone (Gritstone)

Clastic sedimentary rock with iron-rich cement (FeO(OH)·nH2O)

Sand Dollar Fossil (Echinoidea)

Class Echinoidea (likely order Clypeasteroida), CaCO3 (Calcite)

River Pebble (Gravel)

Clastic sedimentary rock (likely Siltstone or Mudstone pebble; SiO2 with various impurities)

Chert (varieties include Flint or Jasper)

Chert (cryptocrystalline quartz; SiO₂)

Geode (Chert/Quartz)

Silicon Dioxide (SiO2)

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Red Siltstone (or Red Shale)

Clastic Sedimentary Rock (Composition: primarily Quartz, Clay minerals, and Hematite Fe2O3)

Chert Nodule

Microcrystalline Quartz (SiO2)

Chert (Common Opal/Agate variety)

Microcrystalline Quartz (SiO2)