Non Geological

Conglomerate

Conglomerate (clastic sedimentary rock)

Azurite with Malachite and Limonite

Azurite Cu3(CO3)2(OH)2 / Malachite Cu2CO3(OH)2

Banded Agate

Chalcedony (Silicon Dioxide, SiO2)

Pink Coral

Corallium rubrum (Calcium Carbonate, CaCO3)

Sandstone (specifically Arkose or Ferruginous Sandstone)

Sandstone (SiO2 with iron oxide inclusions)

Black Freshwater Pearls

Biogenic Calcium Carbonate (Aragonite/Calcite), CaCO3

Sandstone (likely Siltstone variety)

Arenite / Siltstone (primary mineral SiO2)

Chert (with Quartz Veining)

Chert (formula: SiO2)

Quartz Geode

Crystalline Silicon Dioxide (SiO2) in Geode form

Amygdaloidal Basalt with Epidote

Vesicular Basalt with secondary Epidote/Quartz mineral infill

Limonite with Hematite

Limonite (FeO(OH)·nH2O) and Hematite (Fe2O3)

Quartzite with Quartz Vein

Metamorphosed sandstone (SiO2)

Ammonite Fossil

Ammonoidea (typically preserved as Calcite CaCO3 or Pyrite FeS2)

Amygdaloidal Basalt

Amygdaloidal Basalt (Mafic volcanic rock)

Petrified Wood

Silicified Wood (SiO2)

Chalcedony in Host Rock

Chalcedony (SiO2)

Basalt with Limonite stains

Extrusive mafic igneous rock; Limonite (FeO(OH)·nH2O)

Nuummite

Nuummite (complex silicate composed of Anthophyllite and Gedrite, (Mg,Fe)7Si8O22(OH)2)

Biotite Schist

Biotite Schist (Rich in K(Mg,Fe)3AlSi3O10(OH)2)

Wishing Stone with Quartz Veins

Quartzite or Quartz-veined Metamorphic Rock (composed mainly of SiO2)

Banded Calcite (often commercially called 'Mexican Onyx')

Calcium Carbonate (CaCO3)

Conglomerate

Conglomerate (SiO2 dominant in clasts)

Moqui Marble (Ironstone Concretion)

Iron Oxide Concretion (Fe2O3 / FeO(OH))

Heulandite with Stilbite

Heulandite-Ca ((Ca,Na)2-3Al3(Al,Si)2Si13O36·12H2O) and Stilbite-Ca (NaCa4(Si27Al9)O72·28H2O)

Petrified Wood

Silicified Wood (SiO2)

Ironstone Concretion (Moqui Marble)

Iron Oxide Concretion (Fe2O3 / FeO(OH) mixed with SiO2)

Limonite-pseudomorph after Pyrite (Prophecy Stone)

Goethite and Limonite secondary minerals (FeO(OH)·nH2O) replacing Pyrite (FeS2)

Granite Thin Section

Granitic rock (Phaneritic texture)

Garnet Schist

Almandine Garnet in Mica Schist (Fe3Al2(SiO4)3)

Quartz Geode Fragment

Silicon Dioxide (SiO2)

Liesegang Ring Siltstone

Siltstone with iron oxide Liesegang bands

Quartz with Iron Oxide Monzonite or Sandstone contact

Quartz (SiO2) with Limonite/Hematite staining

Jasper with Epidote Vein

Silicon Dioxide (SiO2) with Calcium Aluminum Iron Silicate (Ca2(Al,Fe)3(SiO4)3(OH))

Fossilized Echinoid (Sea Urchin)

Echinoidea (Class), often found as calcitic fossils

Petrified Wood

Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)

Geode Nodules / Chalcedony Geode

Silicon Dioxide (SiO2) - Amorphous to Cryptocrystalline Quartz

Biotite Schist with Garnet

Garnet-Biotite Schist

Sandstone (lithic/greywacke variant)

Clastic sedimentary rock (primarily SiO2 with rock fragments)

Gold Nugget

Native Gold (Au)

Milky Quartz

Silicon Dioxide (SiO2)

White Moonstone (Scolicite or White Feldspar var. )

Lattice-structure Silicate (KAlSi3O8)

Milky Quartz

Silicon Dioxide (SiO2)