Metamorphic Rock (Primarily Composed Of Minerals)

Sandstone

Arenite (primarily SiO2)

Sandstone (Quartzose)

Arenite (primarily SiO2)

Talc

Talc (Mg₃Si₄O₁₀(OH)₂)

Sandstone

Arenite

Granite

Intrusive Felsic Igneous Rock

Greenstone with Epidote or Quartz Vein

Epidiorite or Metabasalt (composed largely of Chlorite, Epidote, and Amphibole)

Basalt with Iron Oxidation

Aphanitic Mafic Igneous Rock (composed primarily of Plagioclase and Pyroxene)

Ironstone Concretion / Goethite Nodules

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

Lapis Lazuli

Na8[Al6Si6O24]n(S,Cl,SO4,OH)2

Not a geological specimen

N/A (man-made object)

Red Shale

Lutite (primarily composed of Hydrous Aluminum Silicates with Hematite staining)

Sandstone

Arenite (composed primarily of SiO2)

Sandstone

Arenite (composed primarily of SiO2)

Shale

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

Sandstone

Quartz Sandstone (predominantly)

Dalmatian Stone

Dalmatian Stone (a peralkaline igneous rock consisting of Feldspar, Quartz, and Arfvedsonite)

Granite Gneiss

Gneiss (High-grade regional metamorphic rock)

Lapis Lazuli

Lazurite-rich metamorphic rock ((Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)

Gneiss (likely)

Gneiss

Sandstone

Arenite (primarily SiO2)

Banded Gneiss

Gneiss (Metamorphic Rock)

Red Sandstone

Arenite (with Iron Oxide / Hematite cementation)

Quartz (likely) or a Quartzite Pebble

Silicon dioxide (SiO2) for quartz. If it's quartzite, it's a metamorphic rock primarily composed of quartz.

Quartzite River Rock

Quartzite (primarily SiO2)

Pebble

Clast (specifically a granule or small pebble)

Shale or Argillite

Shale (fine-grained clastic sedimentary rock) or Argillite (low-grade metamorphic rock derived from shale)

Bauxite

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

Sandstone

Arenite (composed primarily of SiO2)

Siltstone

Siltstone (primarily composed of SiO2)

Sandstone (likely Quartz Sandstone)

Arenite (composed primarily of SiO2)

Sandstone (likely Graywacke or Arkosic varieties)

Arenite (composed primarily of SiO2)

Schist (with Iron Oxide)

Mica Schist

Sandstone (with Feldspathic/Arkose qualities)

Arenite (primarily SiO2 with KAlSi3O8 components)

Quartzite (River Cobble)

Metamorphic Rock (composed predominantly of SiO2)

Sandstone (Quartzose)

Arenite (primarily SiO2)

Assorted Decorative Tumbled Stones (Quartz, Sodalite, Aventurine, Calcite)

Mixed Silicates and Carbonates (SiO2, Na8(Al6Si6O24)Cl2, CaCO3)

Yellow Agate

Silicon Dioxide (SiO2)

Sandstone

Arenite (primarily SiO2)

Sandstone

Arenite (composed primarily of SiO2)

Sandstone

Arenite (primarily SiO2)

Graphic Granite (Zebra Rock)

Pegmatitic Granite (composed of Quartz and K-Feldspar)

Sandstone (Quartzose Sandstone)

Arenite (composed primarily of SiO2)