Sedimentary Rock

Chert (Common Opal/Jasper variety)

Microcrystalline Quartz (SiO2) with hydration

Chert (Iron-Stained)

Microcrystalline Silica (SiO2)

Concretion or Geode (unbroken)

Varied (depending on mineral composition and cementing agent). For quartz-lined geodes, the scientific name of the dominant mineral would be Quartz (SiO2). For calcite-lined geodes, Calcite (CaCO3). Concretions are often composed of cryptocrystalline quartz (chert), calcite, or iron oxides.

Shale or Slate with Quartz Veins

Shale (fine-grained clastic sedimentary rock) or Slate (low-grade metamorphic rock formed from shale) with Quartz (SiO2) veins

Liesegang Ring Siltstone

Siltstone with iron oxide Liesegang bands

Calcite on Limestone (or Fossil)

Calcium Carbonate (CaCO3)

Agatized Chert / Chalcedony

Silicon Dioxide (SiO2)

Chert (often called Flint or Jasper)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (Yellow Jasper variant)

Silicon Dioxide (SiO2)

Chert Pebble/Nodule

Chert (a microcrystalline or cryptocrystalline sedimentary form of quartz, SiO2)

Sandstone (likely Quartzose Sandstone)

Arenite (SiO2 based)

Chert (Field Stone)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Banded Calcite (often sold as 'Mexican Onyx' or 'Green Onyx')

Calcite (Calcium Carbonate, CaCO3)

Chert (Flint)

Microcrystalline Quartz (SiO2)

Chert (Commonly known as Flint)

Microcrystalline Quartz (SiO2)

Chert (often called Flint or Jasper)

Silicon Dioxide (SiO2)

Chert (Jasper/Agate variety)

Microcrystalline Quartz (SiO2)

Ironstone Concretion / Goethite Nodules

Ironstone (composed primarily of Goethite FeO(OH) and Limonite)

Quartz Geode

Silicon Dioxide (SiO2) in a Geode body

Quartz Druzy Geode

Silicon Dioxide (SiO2) - Crystalline Variety

Limonite-stained Chert

Silicon Dioxide (SiO2) with Hydrated Iron Oxide (FeO(OH)·nH2O)

Clay (as a rock-forming material)

Clay minerals (e.g., Kaolinite group, Smectite group, Illite group, Chlorite group)

Red Jasper

Red Jasper (SiO2 with Fe2O3 impurities)

Chert / Flint (a variety of Chert)

Chert (SiO2)

Chert (Jasper-like)

SiO2 (Cryptocrystalline Quartz)

Banded Flint (Polished Stripe Flint)

Silicon Dioxide (SiO2) - variety of Chert

Kambaba Jasper

Stromatolite (Fossilized Algae)

Chert (Chalk-associated Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert / River Jasper

Microcrystalline Quartz (SiO2)

White Jade / White Chalcedony

Nephrite Jade (Ca2(Mg,Fe)5Si8O22(OH)2) or Chalcedony (SiO2)

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Pink Anthracite Coal (dyed)

Anthracite Coal (Artificially Colored)

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Pebble or Cobble (likely composed of sandstone or conglomerate)

Clastic Sedimentary Rock (specific name like sandstone, conglomerate, or breccia would require microscopic analysis of clast size and angularity)

Shale

Fissile Clay-dominant Mudrock (SiO2, Al2O3, K2O, Na2O, CaO, MgO)

Red Jasper

Silicon Dioxide (SiO2) with Hematite impurities

Dendritic Agate (specifically Orange/Tumbled)

Silicon Dioxide (SiO2) with Oxide Inclusions

Quartzite with inclusions

Quartzite (primarily SiO2)

Banded Agate (Onyx variety)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chert (Septarian Nodules / Weathered Silex)

Microcrystalline Quartz (SiO2)

Anthracite Coal

Anthracite (a variety of coal, predominantly carbon)

Ironstone Concretion (Moqui Marble)

Iron-oxide Concretion (Hydrated ferric oxide, Fe2O3·nH2O)