Sedimentary (Alluvial Deposit)

Sandstone (lithic/greywacke variant)

Clastic sedimentary rock (primarily SiO2 with rock fragments)

Agate (specifically a Blue Agate Geode Slice)

Chalcedony (cryptocrystalline variety of Quartz); SiO2

Jasper (Iron-rich Chert)

Silicon Dioxide (SiO2) with impurities of Hematite or Goethite

Chert (Chalcedony/Jasper)

Microcrystalline Quartz (SiO2)

Yellow Jasper

Silicon Dioxide (SiO2) with iron inclusions

Grey Chalcedony

Silicon Dioxide (SiO2)

Yellow Jasper (Mookaite style)

Silicon Dioxide (SiO2) with Goethite/Hematite inclusions

Jasper (specifically Yellow Jasper and Red Jasper)

Silicon Dioxide (SiO2) with iron oxide inclusions

Jasper (likely Ocean Jasper or Variegated Jasper)

Silicon Dioxide (SiO2) with impurities

Geode with Iron-Stained Quartz/Calcite

Silicon Dioxide (SiO2) or Calcium Carbonate (CaCO3) in Sedimentary Matrix

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

Zebra Jasper

Silicon Dioxide (SiO2) with impurities; typically a form of Chalcedony/Microcrystalline Quartz

Red Jasper (Chert)

Silicon Dioxide (SiO2)

Fancy Jasper

Chalcedony (cryptocrystalline quartz) with inclusions

Yellow Jasper

Silicon Dioxide (SiO2) with Goethite/Iron oxide inclusions

Limonite (after Pyrite Pseudomorph)

Limonite (Hydrated Iron Oxide Mixture, FeO(OH)·nH2O)

Limestone

Sedimentary Calcium Carbonate (CaCO3)

Jasper with Hematite inclusions

Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3)

Petrified Wood

Silicified Wood (primarily SiO2 - Silicon Dioxide)

Rugose Coral (Horn Coral)

Order Rugosa (extinct fossilized coral)

Chert (Jasper variety)

Silicon Dioxide (SiO2) with iron oxide impurities

Red Sandstone

Arenite (Ferruginous Sandstone)

Chert (Jasper)

Microcrystalline Quartz (SiO2)

Chert (Jasper/Quartzite)

Microcrystalline Silicon Dioxide (SiO2)

Glauconitic Sandstone

Glauconitic Sandstone (complex silicate formula: (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)

Crushed Stone / Greywacke

Greywacke (Indurated Sandstone)

Banded Sandstone

Arenite (with iron oxide banding)

Ironstone (likely Limonite or Goethite nodule)

Hydrothermally altered Ferric Hydroxide (FeO(OH)·nH2O)

Clear Quartz

Silicon Dioxide (SiO2)

Hematite

Iron(III) oxide (Fe2O3)

Limestone with Calcite Veins

Sedimentary Calcium Carbonate (CaCO3)

Sandstone (likely Quartzose Sandstone)

Arenite (SiO2 principal composition)

Bauxite

Bauxite (Al2O3·nH2O)

Chert (Flint)

Chert (SiO2)

Sandstone (likely Quartzose Sandstone)

Arenite (composed primarily of SiO2)

Sandstone (Gneissic or Banded)

Clastic Sedimentary Rock (composed predominantly of SiO2)

Glauconite (Glauconitic Sandstone)

Glauconite [(K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2]

Limonite (Iron Ore)

FeO(OH)·nH2O (Hydrous ferric oxide)

Satin Spar (Gypsum)

Calcium Sulfate Dihydrate (CaSO4·2H2O)

Sandstone (Quartzose)

Arenite (predominantly SiO2)

Sandstone

Arenite (composed primarily of SiO2)

Sandstone (with Iron Staining)

Clastic sedimentary rock (primarily SiO2)