Mineral, Possibly Rock Fragment Containing A Mineral

Man-made Synthetic Material (Plastic/Composite)

Acrylonitrile Butadiene Styrene (ABS) or High-Impact Polystyrene (HIPS)

Sandstone

Arenite (SiO2 based)

Quartz Geode / Druzy Quartz

Silicon Dioxide (SiO2)

Sandstone (likely Ferruginous)

Arenite (SiO2 with iron oxide impurities)

Granite Pebble

Granite (composed primarily of Quartz, Feldspar, and Mica)

Sandstone (Fossiliferous)

Clastic Sedimentary Rock (primarily SiO2)

Sandstone (with Limonite staining)

Arenite (primarily SiO2 with FeO(OH)·nH2O)

Sandstone (Quartzose Sandstone)

Arenite

Amber

Succinite (fossilized tree resin)

Quartz (likely) or a Quartzite Pebble

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

Jasper or Chert

Silicon Dioxide (SiO2)

Conglomerate

Conglomerate rock

Limonite with Trace Fossils

Hydrous Iron Oxide Mixture (FeO(OH)·nH2O)

Sandstone

Arenite (SiO2 primarily)

Sandstone (with potential fossil inclusions)

Clastic sedimentary rock (primarily SiO2)

Conglomerate

Conglomerate (a clastic sedimentary rock)

Sandstone

Arenite (primarily SiO2)

Granitic Pegmatite (River Rock specimen)

Granite / Pegmatite (composed of SiO2, KAlSi3O8, and NaAlSi3O8)

Sandstone (likely Arkosic or Lithic Sandstone)

Arenite (SiO2 based with mineral inclusions)

Sandstone

Clastic sedimentary rock (primarily SiO2)

Quartz / Common Opal Transition

Silicon Dioxide (SiO2)

Limestone with Calcite Veins

Sedimentary Calcium Carbonate (CaCO3)

Sandstone (Ferruginous)

Arenite (composed primarily of SiO2 with Fe2O3 cement)

Calcite (or Alabaster, if truly carved)

Calcium Carbonate (CaCO3)

Sandstone (Ferruginous)

Arenite (Fe-rich)

Agate (or Banded Agate)

Agate (a variety of Chalcedony, which is a cryptocrystalline form of Quartz); Chemical Formula: SiO₂ (Silicon Dioxide)

Sandstone (Painted)

Arenite (primarily SiO2)

Pebble (likely a type of sandstone or quartzite pebble)

Clastic Sediment (specifically, a rudite-sized clast). If the pebble is composed of a specific rock type, its scientific name would be that rock type (e.g., 'Quartzite pebble', 'Granite pebble', 'Chert pebble'). Given its appearance, it is likely a metamorphic quartzite pebble or a hard sandstone pebble.

Weathered Sandstone with Algae Growth

Arenite

Sandstone (likely Fossiliferous Sandstone)

Clastic sedimentary rock (primarily SiO2)

Amethyst (Agate/Chalcedony variety)

Silicon Dioxide (SiO2) with iron impurities

Pegmatite

Pegmatitic Granite

Sandstone (likely Greywacke variant)

Arenite

Sandstone (likely Quartzose Sandstone)

Arenite (composed primarily of SiO2)

Sandstone (with Limonite staining)

Arenite (primarily SiO2 with FeO(OH)·nH2O)

Greywacke (River Pebble with Quartz Veins)

Greywacke (Indurated Sandstone); Veins: SiO2 (Quartz)

Sandstone (Ferruginous)

Arenite with Iron Oxide cement (SiO2 + Fe2O3)

Quartz Geode Fragment

Silicon Dioxide (SiO2)

Sandstone

Arenite (Clastic Sedimentary Rock)

Ironstone (likely siderite or goethite-rich siltstone)

Ferruginous Siltstone

Mica Schist

Mica Schist (primarily Muscovite or Biotite sheet silicates)

Red Sandstone

Arenite (primarily Quartz with Hematite cement)