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

Orange Calcite

Calcium Carbonate (CaCO3)

Quartz Geode

Silicon Dioxide (SiO2)

Septarian Nodule (Dragon Stone)

Septarian concretion (composition: CaCO3 - Calcite, Aragonite, and Siderite/Limestone)

Sandstone (Quartzose Sandstone)

Clastic Terrigenous Sedimentary Rock (primarily SiO2)

Weathered Sandstone with Algae Growth

Arenite

Limestone

Sedimentary Calcium Carbonate (CaCO3)

Chert (Field-collected specimen)

Chert (Crystalline Silica, SiO2)

Quartz (Milky/Clear Quartz)

Silicon Dioxide (SiO2)

Geode with Quartz and possibly Jasper/Hematite

Quartz (SiO2) and Chalcedony (cryptocrystalline SiO2), possibly stained by iron oxides

Limestone

Calcium Carbonate (primarily CaCO3 as Calcite or Aragonite)

Chert (White Chert / Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Nodule)

Chert (Silicon Dioxide, SiO2)

Chert (Flint)

Chert (Microcrystalline Quartz, SiO2)

Sandstone (likely Arkosic or Quartzose)

Sandstone (SiO2 dominated)

Banded Agate (River Stone)

Agate (Silicon Dioxide - SiO2)

Chert (Flint)

Chert (Silicon Dioxide, SiO2)

Chert (Flint)

Silicon Dioxide (SiO2)

Chert Nodule (Flint)

Silicon Dioxide (SiO2)

Chert Concretion (with typical hematite/limonite staining)

Sedimentary Concretion (SiO2 with FeO(OH)⋅nH2O)

Chert (specifically Flint or Jasper variant)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (with Limestone/Carbonate matrix)

Sedimentary cryptocrystalline silica (SiO2)

Sandstone with Magnetite and Iron Staining

Clastic Sedimentary Rock (contains Fe3O4 and Limonite/Hematite)

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Sandstone (Quartzite-rich River Cobble)

Clastic sedimentary rock (primarily SiO2)

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Chert / Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Aragonite Star Cluster

Aragonite (Calcium Carbonate, CaCO3)

Sandstone (lithic wake/graywacke variety)

Arenite/Greywacke (SiO2 with lithic fragments)

Limestone with Chert

Sedimentary Rock (CaCO3 with SiO2 inclusions)

Chert (Common Opal variant)

Microcrystalline Quartz (SiO2)

Ferruginous Sandstone

Sandstone with Iron Oxide (Limonite/Goethite)

Chert (Nodule)

Microcrystalline Quartz (SiO2)

Schist with Biotite Inclusion

Biotite-bearing Mica Schist (K(Mg,Fe)3AlSi3O10(F,OH)2)

Sandstone

Arenite (primarily SiO2)

Chert (Tan/Buff Chert)

Microcrystalline Quartz (SiO2)

Granular Sandstone

Arenite (variable composition, primarily SiO2)

Ferruginous Quartz (Carnelian-tinted Quartz)

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Sandstone (with potential iron-oxide weathering)

Arenite (SiO2 based)

Quartz (specifically Citrine or Yellow Quartzite pebble)

Silicon Dioxide (SiO2)

Sandstone (Quartzite-rich Pebble)

Arenite (primarily SiO2)

Sandstone (Quartzose Sandstone)

Clastic Sedimentary Rock (primarily SiO2)

Basalt with Amygdaloidal Inclusions

Aphanitic Mafic Volcanic Rock (Basalt)