Rock (Likely Sedimentary)

Gneiss (specifically a weathered or stream-worn specimen)

Gneiss (Foliated Metamorphic Rock)

Sandstone (likely Quartzose Sandstone)

Arenite

Jasper with Quartz Vein

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Ironstone (likely Limonite or Goethite)

Ferruginous sedimentary rock (FeO(OH)·nH2O)

Banded Rock (likely Quartz-rich)

Uncertain, likely a Metamorphic Rock (e.g., Gneiss or Schist) with prominent Quartz and other minerals

Fossil Shell (Bivalve)

Class Bivalvia (Likely a member of the Ostreidae or Gryphaeidae family), CaCO3

Sand Dollar Fossil (Echinoidea)

Class Echinoidea (likely order Clypeasteroida), CaCO3 (Calcite)

Yellow Agate

Chalcedony (cryptocrystalline Quartz), SiO2

Limestone

Calcium Carbonate (CaCO3)

Not a geological specimen

N/A (man-made object)

Piddock bored rock (likely Mudstone or Shale)

Ichnofossil (Gastrochaenolites borings) in Fine-grained Sedimentary Rock

Sandstone (Muddy/Silty Variety)

Arenite with high silt/clay content (clastic sedimentary rock)

Petrified Wood

Silicified Wood (SiO2)

Chert (Jasper variety) with Iron Oxide staining

Cryptocrystalline Quartz (SiO2) with Goethite/Limonite impurities

Pebble (likely Quartz or Chert)

SiO₂ (Silicon Dioxide) - referring to the likely main mineral composition, Quartz. If it's chert, the scientific name remains SiO₂ with a microcrystalline structure.

Jasper with Quartz inclusions

Silicon Dioxide (SiO2) - Microcrystalline Chalcedony

Banded Metamorphic Rock (likely Quartzite or Serpentinite/Soapstone)

Metamorphic Rock (possibly a banded Quartzite or a foliated Serpentinite/Talc Schist based on appearance, general term for such a rock is 'Banded Metamorphic Rock' or 'Gneiss' if pronounced banding of different minerals)

Chert (with Quartz vein)

Chert (Silicon Dioxide, SiO2)

Milky Quartz in Conglomerate Matrix

Silicon Dioxide (SiO2) within Clastic Sedimentary Rock

Greywacke (River Pebble)

Greywacke sandstone with quartz veining

Chert Pebble (with Quartz Vein)

Chert (Cryptocrystalline Silica - SiO2)

Banded Gneiss

Gneiss (High-grade regional metamorphic rock)

Granite with Epidote

Granite, containing quartz, feldspar, and epidote

Quartz (likely) / Siliceous rock with quartz phenocrysts (if a rock fragment)

Quartz (SiO₂)

Jasper

Silicon Dioxide (SiO2)

Ironstone Concretion (likely)

Goethite/Hematite/Limonite cemented sediment

Quartz (Milky/Smoky variety on matrix)

Silicon Dioxide (SiO2)

Sandstone (likely River-tumbled Picture Sandstone)

Arenite (predominantly SiO2 with iron oxide impurities)

Basalt with Jasper Veining

Basaltic Rock with Cryptocrystalline Quartz (SiO2)

Basalt with Iron Oxidation (Lattice/Veined)

Mafic Volcanic Rock (principally Plagioclase and Pyroxene)

Biotite Schist (likely)

Biotite Schist (rock), Biotite (mineral)

Porphyritic Basalt (River Rock)

Porphyritic Basalt

Banded Chert (Jasper)

Silicon Dioxide (SiO2)

Garnetiferous Pegmatite

Pegmatite with Almandine Garnet and Muscovite

Banded Gneiss

Gneiss (High-grade regional metamorphic rock)

Fossiliferous Rock (likely Dinosaur Fossil in Matrix)

Permineralized Vertebrate Fossil (Calcium Carbonate/Silica replaced bone material)

Undetermined Due to Blur (Possible Flesh-Tone Mineral)

Unknown (Insufficient Visual Clarity)

River Stone (likely Mudstone or Siltstone)

Lutite (Clastic sedimentary rock composed of clay and silt-sized particles)

Green Chalcedony (likely Green Agate or Chrysoprase)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Note regarding baguette production (not a rock)

Digital text image - Somali language

Quartz Geode Fragment

Silicon Dioxide (SiO2)

Chert (Nodule / Geode fragment)

Microcrystalline Quartz (SiO2)