Igneous And Fossil

Slate

Foliated low-grade metamorphic rock

Ironstone Concretion (Ironstone Gourd)

Limonite/Goethite Concretion (FeOO(H))

Calcareous Tufa / Limestone Fragment

Calcium Carbonate (CaCO3)

Fossilized Shark Tooth

Fossilized elasmobranch tooth (Apatite/Calcium Phosphate)

Shale

Fissile Mudstone (primarily composed of phyllosilicate minerals like kaolinite, montmorillonite, and illite)

Limestone

Sedimentary Calcium Carbonate (CaCO3)

Shale

Fissile mudrock (composed of clay-sized particles and detrital grains)

Sandstone

Arenite (primarily SiO2)

Chert (with inclusions)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Ironstone (Limonitic Sandstone)

Ferruginous Sandstone (rich in Limonite: FeO(OH)·nH2O)

Siltstone

Siltstone (primarily SiO2 with Al2O3 and Fe2O3)

Fossilized Shark Tooth

Carcharodon carcharias (fossilized) / Hydroxyapatite permineralized with silica or iron

Fossilized Crinoid Stem

Class Crinoidea (Echinodermata)

Shale (or Mudstone)

Laminose Mudrock (composition: clay minerals, quartz, and mica flakes)

Sandstone

Sandstone (clastic sedimentary rock)

Limestone (with possible Manganese oxide inclusions)

Sedimentary Calcium Carbonate (CaCO3)

River Pebble (Quartz/Chert)

Silicon Dioxide (SiO2)

Sandstone (Ferruginous)

Clastic sedimentary rock (primarily SiO2 with Fe2O3 cement)

Sandstone (Quartzose)

Arenite (primarily SiO2)

Limestone

Calcium Carbonate (CaCO3)

Sandstone

Arenite (SiO2 based)

Limestone

Limestone (Calcium Carbonate - CaCO3)

Sandstone

Clastic sedimentary rock (primarily SiO2)

Sandstone with Vitrinite/Coal inclusions

Arenite with Carbonaceous inclusions

Sandstone (Quartzose Sandstone)

Arenite (primarily SiO2)

Limestone

Calcium Carbonate (CaCO3)

Coal (Bituminous)

Sedimentary carbonaceous rock

River Cobble (Conglomerate context)

Unconsolidated Fluvial Alluvium (comprised of various lithologies like Quartzite, Granite, or Basalt)

Sandstone (with cross-bedding)

Arenite (composed primarily of Quartz: SiO2)

Sandstone (Red Sandstone)

Arenite

Sandstone (Quartzose Sandstone)

Clastic sedimentary rock (SiO2 dominated)

Sandstone (clastic)

Clastic Sedimentary Rock (primarily composed of SiO2)

Siltstone

Siltstone (composed of microscopic silt-sized particles of quartz and feldspar)

Shale with Plant Fossils / Carbonaceous Shale

Laminated Mudrock (Siliciclastic)

Chert (Nodular)

Chert (SiO2 - Microcrystalline Quartz)

Limestone

Calcium Carbonate (CaCO3)

Chert / Flint

Microcrystalline Silica (SiO2)

Quartzite with Vugs

Metamorphosed Quartz Sandstone (SiO2)

Sandstone (Quartzite texture)

Clastic sedimentary rock (primarily SiO2)

Chert (Flint)

Microcrystalline Quartz (SiO2)

Sandstone (with manganese staining)

Clastic sedimentary rock (primarily SiO2)

Chalcedony (specifically Agate or Common Opal variety)

Cryptocrystalline Silica (SiO2)