Sedimentary (Chemically Precipitated) Or Metamorphic

Celestite (Celestine)

Strontium sulfate (SrSO4)

Quartzite

Metamorphic Quartzite (SiO2)

Light Blue Quartzite Pebbles / Decorative Stone

Metamorphic Quartzite (SiO2)

White Quartz

Quartz (SiO2)

Rounded gray limestone pebble with a calcite vein

Calcitic limestone, composed predominantly of calcite (CaCO₃), locally cut by a white calcite vein

Vein-filled Sedimentary Rock

Silicified sedimentary rock with quartz/calcite vein

Banded Agate (River Pebble)

Silicon Dioxide with impurities (SiO2)

Limestone with Weathering Rind

Calcium Carbonate (CaCO3) - Bioclastic or Micritic Limestone

Chert (White Variety)

Microcrystalline Silica (SiO2)

Chert (Flint/Jasper)

Silicon Dioxide (SiO2)

Chert (and Chert-based Jasper)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Quartzite (or Engineered Quartz Stone)

SiO2 (Silicon Dioxide)

Quartzite Pebble

Quartzite (SiO2)

Chert (White/Light Tan)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Jasper / Chert (Red)

Cryptocrystalline quartz (SiO2)

Banded Iron Formation (BIF) / Tiger Iron

Ferruginous Chert (primarily Quartz [SiO2] and Hematite/Magnetite [Fe2O3/Fe3O4])

Quartzite Pebble

Metamorphic Quartzite

Quartzite Pebble

Metamorphic Quartzite

Quartzite Pebble

Metamorphic Quartzite

Quartzite Pebble

Metamorphic Quartzite

Quartz on Host Rock

Silicon Dioxide (SiO2)

Limestone

Calcium Carbonate (CaCO3)

Pale green tumbled mineral fragment, likely serpentine or green calcite

Probable serpentine-group mineral (Mg3Si2O5(OH)4) or, less likely, calcite (CaCO3); identification is uncertain from the photograph

Chert / Flint

Silicon dioxide (SiO2)

Chert (Jasper/Agate variety)

Microcrystalline Quartz (SiO2)

Chert (Flint)

Chert (Cryptocrystalline silicon dioxide, SiO2)

Chert (White Chert/Flint)

Chert (Microcrystalline or Cryptocrystalline Quartz, SiO2)

Chert Pebble

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (River Pebble)

Chert (Silicon Dioxide, SiO2)

Chert (variously identified as Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert Nodule (Commonly known as a Flint or River Cobble)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (varieties: Flint or Chalcedony)

Microcrystalline Quartz (SiO2)

Chert (specifically Banded Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Iron-stained garnet-bearing rock, possibly almandine garnet

Garnet-group silicate, likely almandine (Fe₃Al₂Si₃O₁₂), in a quartz–iron-oxide matrix

Quartz pebble

Silicon dioxide (SiO2)

Quartzite

Quartzite (SiO2 composition)

Specular Hematite

Hematite (Fe2O3)

Nephrite Jade

Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)

Limestone

Calcium Carbonate (CaCO3)

Banded Agate

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Flint / Chert

Silicon dioxide (Microcrystalline Quartz, SiO2)

Chert (Jasper/Mudstone variety with Oxidation)

Silicon dioxide (SiO2)