Not A Natural Rock (Man Made Composite)

Slate

Slate (Low-grade foliated metamorphic rock)

Pink Dyed Agate (Pink Agate Slice)

Silicon Dioxide (SiO2) - Chalcedony / Cryptocrystalline Quartz

Shale

Fissile Mudrock (Clay-rich Sedimentary Rock)

Shale

Mudstone/Shale

Fulgurite

Fulgurite (Lechatelierite-rich fused silica)

Milky and Citrine-type Quartz

Silicon Dioxide (SiO2)

Druzy Quartz Geode (likely Smokey Quartz variety)

Silicon Dioxide (SiO2) - specifically a geode formation lined with druzy quartz crystals, with a likely brownish hue indicating smokey quartz.

Turquoise

CuAl6(PO4)4(OH)8·4H2O (Hydrated copper and aluminium phosphate)

Quartz Geode (Smoky Quartz)

Silicon Dioxide (SiO2)

Granite

Phaneritic Intrusive Igneous Rock (composed of Quartz, Feldspar, and Mica)

Quartz Vein with Iron Staining

Silicon Dioxide (SiO2) with limonite/hematite staining

Turquoise

Hydrated phosphate of copper and aluminium - CuAl6(PO4)4(OH)8·4H2O

Sandstone

Sandstone (arenite is a more specific geological term for a clean sandstone, while wacke refers to a dirty sandstone with significant matrix)

Pumice

Pumicite (Amorphous Volcanic Glass)

Shale

Fissile Mudstone (primarily composed of clay minerals and quartz grains)

Milky Quartz

Silicon Dioxide (SiO2)

Marble

Marble (metamorphosed limestone/dolostone). Predominantly composed of Calcite (CaCO3) for marble derived from limestone, or Dolomite (CaMg(CO3)2) for marble derived from dolostone.

Jasper Breccia

Brecciated Jasper (Silicon Dioxide with Iron Oxide inclusions, SiO2)

Blue Chalcedony (Tumbled)

Silicon Dioxide (SiO2)

Shale

Fissile Mudstone (primarily composed of clay minerals and quartz)

Granite

Phaneritic plutonic rock (dominated by SiO2, Al2O3, K2O, Na2O)

Shale or Argillite

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

Ferruginous Sandstone with Quartz Inclusions

Clastic Sedimentary Rock (Iron-rich Sandstone)

Painted Garden Rock (likely Granite or Limestone base)

Silicon Dioxide (SiO2) / Calcium Carbonate (CaCO3) based substrate with Acrylic/Enamel pigments

Amethyst (Faceted)

Amethyst (Silicon Dioxide with iron impurities, SiO2)

Shungite (Noble/Type II)

Non-crystalline carbon (Fullerene-bearing carbonaceous rock)

Granite

Granite (Felsic intrusive igneous rock)

Green Aventurine

Silicon Dioxide (Quartz variety) with Fuchsite inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)

Clear Quartz (Rock Crystal)

Quartz (Silicon Dioxide, SiO2)

Pumice

Pumice (Amorphous volcanic glass)

Granite

Intrusive Felsic Igneous Rock

Herkimer Diamond

Double-Terminated Quartz (SiO2)

Clear Quartz

Silicon Dioxide (SiO2)

Carnelian

Carnelian (Silicon Dioxide - SiO2)

Rough Corundum (likely Sapphire/Zircon-bearing)

Aluminium Oxide (Al2O3)

Gold

Aurum (Au)

Turquoise

Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]

Sandstone

Sandstone (Clastic Sedimentary Rock)

Greywacke (River Siltstone)

Lithic Wacke (Sandstone subfamily)

Dyed Agate

Silicon Dioxide (SiO2) - variety Chalcedony

Sandstone (Weathered Coastal Boulder)

Arenite (composed primarily of SiO2)

Turquoise

Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)