Sedimentary (Chemically Precipitated)

Orange Calcite

Calcium Carbonate (CaCO3)

Orange Calcite

Calcium Carbonate (CaCO3)

Chert / Flint

Silicon Dioxide (SiO2)

Chert (Nodule)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Weathered quartz-rich pebble

Likely massive quartz (SiO₂), possibly quartzite or silicified rock

Chert

Chert (Microcrystalline Quartz, SiO2)

Quartz vein in weathered host rock

Quartz (SiO₂), likely in a weathered metamorphic or igneous matrix

Chert (Gravel)

Chert (Microcrystalline Silicon Dioxide, SiO2)

Chert (Flint)

Silicon Dioxide (SiO2)

Travertine (Tufa)

Chemical Sedimentary Rock (CaCO3)

Travertine (Tufa)

Chemical Sedimentary Limestone (CaCO3)

Chert (River Pebble)

Silicon Dioxide (SiO2)

Chert (Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Banded iron formation (BIF) fragment

Metamorphosed iron formation; alternating hematite/magnetite and chert (SiO₂) layers

Chert / Flint

Microcrystalline quartz (SiO2)

Flint / Chert Pebble

Microcrystalline quartz (SiO2)

Chert (specifically Gray Chert)

Chert (SiO2)

Chert (Flint/Jasper variety)

Microcrystalline Quartz (SiO2)

Chert

Microcrystalline Quartz (SiO2)

Chert (Quartzite Pebble)

Microcrystalline Quartz (SiO2)

Agate Geode

Silicon Dioxide (SiO2) - Chalcedony variety

Chert (Flint)

Microcrystalline Quartz (SiO2)

Dyed Agate Geode

Silicon Dioxide (SiO2) - Banded Chalcedony

Banded iron formation (ironstone), likely hematite–magnetite-rich

Banded iron formation (BIF); chiefly hematite (Fe₂O₃), magnetite (Fe₃O₄), and quartz (SiO₂)

Chert (specifically Flint or Common Opal)

Silicon Dioxide (SiO2)

Chert / Flint Nodule

Microcrystalline quartz (SiO2)

Chert (Nodular Chert)

Silicon Dioxide (SiO2)

Red Jasper

SiO2 (Microcrystalline Quartz)

Jasper with Quartz Veining

Silicon Dioxide (SiO2) - Opaque cryptocrystalline variety of Quartz

Jasper

Microcrystalline Quartz (SiO2)

Jasper

Microcrystalline quartz (SiO2)

Jasper

Microcrystalline quartz (SiO2)

Jasper

Microcrystalline Quartz (SiO2)

Jasper Pebble

Microcrystalline Quartz (SiO2)

Quartz Geode

Silicon Dioxide (SiO2)

Jasper

Microcrystalline quartz (SiO2)

Hematite

Iron(III) oxide (Fe2O3)

Jasper

Microcrystalline Quartz (SiO2)

Rhodochrosite

Manganese Carbonate (MnCO3)

Jasper

Microcrystalline Quartz (SiO2)

Jasper

Silicon dioxide with impurities (SiO2)

Quartz

Silicon Dioxide (SiO2)