This Appears To Be A Man Made Metallic Object, Likely Jewelry, Not A Natural Rock, Mineral, Or Geological Specimen.

Carnelian

Carnelian (SiO2 with Iron Oxide impurities)

River Stone (likely Siltstone or fine-grained Sandstone)

Clastic Sedimentary Rock (Lithic Wacke / Siltstone)

Tree Agate (or Moss Agate)

Dendritic Agate (Silicon Dioxide - SiO2)

Hematite

Iron(III) oxide (Fe2O3)

Chert (Flint)

Silicon dioxide (SiO2)

Granite

Granite (a common igneous rock)

Rose Quartz

Quartz (Silicon Dioxide - SiO2) with trace amounts of titanium, iron, or manganese

Jade

Jadeite or Nephrite (both are commonly referred to as 'jade'). Jadeite: NaAlSi2O6; Nephrite: Ca2(Mg,Fe)5Si8O22(OH)2.

Conglomerate

Conglomerate (clastic sedimentary rock)

Banded Gneiss (River Cobble)

Gneiss (a high-grade metamorphic rock)

Granite

Intrusive igneous rock (Acidic)

Citrine

Citrine (Silicon Dioxide - SiO2)

Amethyst

Amethyst (Silica mineral, SiO2)

Quartz (Clear / Rock Crystal)

Silicon Dioxide (SiO2)

Lapis Lazuli (in Matrix)

Na8[Al6Si6O24]S2 (Lazurite as the primary component)

Dalmatian Stone (often misnamed Dalmatian Jasper)

Aplite (with hornblende/arfvedsonite inclusions)

Pyrite

Iron Sulfide (FeS2)

Pyrite

Iron Disulfide (FeS2)

Pyrulite (Pyrite / Chalcopyrite)

Iron Sulfide (FeS2) or Copper Iron Sulfide (CuFeS2)

Amethyst

SiO2 (Silicon Dioxide)

Sandstone (lithic/greywacke variant)

Clastic sedimentary rock (primarily SiO2 with rock fragments)

Amethyst

Amethyst (Silicon Dioxide, SiO2 + Fe4+ impurities)

Quartz Geode

Silicon Dioxide (SiO2) within a secondary sedimentary structure

Quartz with inclusions (likely Tourmaline or Biotite)

Silicon Dioxide (SiO2)

Gold Ore in Quartz

Auriferous Quartz (SiO2 with Au inclusions)

Schist

Mica Schist

Green Aventurine

Silicon Dioxide (SiO2) with Fuchsite inclusions

Sandstone with Liesegang Rings

Arenite with Iron Oxide Liesegang Banding

Quartz (variety of colors)

SiO2 (Silicon Dioxide)

Slag

Ferrous Slag (Siliceous industrial waste)

Milky Quartz

Silicon Dioxide (SiO2)

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Citrine Quartz

Quartz (SiO2) - specifically, a variety of macrocrystalline quartz

Quartz Pebble (Geode-like)

Silicon Dioxide (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Tumbled Stone Collection (featuring Tiger's Eye, Rose Quartz, and Moss Agate)

Mixed Silicates and Oxides (predominantly SiO2 group minerals)

Fluorite (Blue)

Calcium Fluoride (CaF2)

Iron Ore / Ironstone Concretion

Mixture of iron oxide/hydroxide minerals, likely some combination of Hematite (Fe2O3), Goethite (α-FeOOH), and Limonite (a general term for hydrated iron oxides of variable composition) or potentially Bauxite (a mixture of aluminum hydroxides, often with iron oxides, (Al(OH)3) and FeO(OH)). The visual characteristics strongly suggest iron-rich material.

Green Fluorite

Fluorite (Calcium Fluoride, CaF2)

Diamond

Diamond (C)

Agate (specifically Waterline or Onyx-type Agate)

Silicon Dioxide (SiO2) - variety Chalcedony