Sedimentary Rock (Specifically A Clastic Sedimentary Rock Formed Into A Cobble)

Chert (River Pebble)

Microcrystalline Quartz (SiO2)

Banded Gneiss

Gneiss (complex metamorphic silicate rock)

Fossil Shell in Sedimentary Matrix

Bivalvia (fossil) in Calcium Carbonate Matrix

Limestone

Calcium Carbonate (CaCO3)

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Fossilized Favosites (Honeycomb Coral)

Favosites (extinct genus of tabulate coral)

Geode with Iron-Stained Quartz/Calcite

Silicon Dioxide (SiO2) or Calcium Carbonate (CaCO3) in Sedimentary Matrix

Jet

Lignite (Anthracite-grade compact coal)

Marble

Marble (metamorphosed limestone or dolostone), primarily composed of calcite (CaCO3) or dolomite (CaMg(CO3)2)

Brecciated Jasper

Silicon Dioxide (SiO2) with varying mineral inclusions (Iron Oxide, Hematite, Clay)

Chert / Flint

Chert (Silicon Dioxide, SiO2)

Ironstone Concretion

Siderite or Limonite Concretion

Chert (Nodule)

Silicon Dioxide (SiO2)

Red Brecciated Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

Jasper

Silicon Dioxide (SiO2)

Travertine

Travertine (CaCO3 - Calcium Carbonate)

Dalmatian Stone

Dalmatian Jasper (Peralkaline Quartz-Feldspar Rock)

Turquoise (set in silver jewelry)

Turquoise - CuAl6(PO4)4(OH)8·4H2O (Hydrated copper and aluminum phosphate)

Turquoise

CuAl6(PO4)4(OH)8·4H2O

Schist

Mica Schist

Bauxite

Bauxite (Mixture of Al(OH)3, AlO(OH), and Fe2O3)

Fossilized Coral

Cnidaria (Anthozoa), often replaced by Calcium Carbonate (CaCO3) or Silica (SiO2)

Quartzite Pebble

Quartzite (SiO2)

Chert (Jasper/Flint variety)

Microcrystalline quartz (SiO2)

Quartz (specifically Citrine or Yellow Quartz)

Silicon Dioxide (SiO2)

River Pebble (Quartz-rich)

Silicon Dioxide (SiO2) with various inclusions

Painted River Pebble (likely Basalt or Greywacke)

Aphanitic Lithic Clast with Anthropogenic Pigment coating

Chalcedony (Botryoidal)

Silicon Dioxide (SiO2)

Chalcedony (Agate/Carnelian precursor)

Chalcedony (Silicon Dioxide, SiO2)

Dalmatian Stone

Peralkaline Quartz-Feldspar Porphyry with Arfvedsonite

Tree Agate

Silicon Dioxide (SiO2) - Dendritic Agate/Chalcedony

Garnet Schist

Almandine-Garnet Mica Schist

Carnelian (Orange Agate)

Silicon Dioxide (SiO2)

Blue Agate (Dyed)

Silicon Dioxide (SiO2)

Fluorite (Rainbow Fluorite)

Calcium Fluoride (CaF2)

Turquoise

CuAl6(PO4)4(OH)8·4H2O (Hydrated copper and aluminium phosphate)

Bauxite

Bauxite (Mixture including Gibbsite Al(OH)3, Boehmite γ-AlO(OH), and Diaspore α-AlO(OH))

Wonderstone (Banded Rhyolite)

Rhyolite (Silicon Dioxide with Iron Oxide impurities)

Banded Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Boxwork Siderite or Sepatarian Nodule Weathering

Siderite (FeCO3) with secondary mineralization or Boxwork Geode fragment

Sandstone

Arenite (SiO2 based)

Geode (unopened)

Calcedony-lined Geode (SiO2)