Man Made Composite (Lithified Equivalent Of Sedimentary)

Biotite granite (weathered granitic rock)

Granite; chiefly quartz (SiO₂), feldspar, and biotite mica

Polymictic breccia, possibly volcanic breccia

Polymictic clastic breccia; likely a matrix-supported breccia containing lithic fragments, quartz, feldspar, and dark mafic minerals

Fossilized Ripple Marks or Stromatolite

Sedimentary ripple mark imprint / Biosedimentary structure

Fossiliferous Limestone

Biomicrite / Fossiliferous Limestone (CaCO3)

Brain Coral Fossil

Family Mussidae or Merulinidae (Order Scleractinia)

Fossil Brachiopod or Mollusk Cast

Phylum Brachiopoda / Mollusca internal mold

Conglomerate

Conglomerate (Clastic sedimentary rock)

Chalk

Micrite (primarily Calcium Carbonate, CaCO3)

Banded sandstone pebble

Quartz-rich lithic sandstone; exact provenance and composition require testing

Chert (containing Iron Oxide spots)

Microcrystalline Quartz (SiO2)

Fossiliferous Limestone

Biogenic Limestone (CaCO3)

Fossilized Brachiopod

Phylum Brachiopoda (Calcium Carbonate/Silica replacement)

Sandstone (Iron-stained)

Clastic sedimentary rock (primarily SiO2 with Fe2O3 staining)

Terracotta (Man-made ceramic brick fragment)

Baked clay / High-iron ceramic (Silicate-based ceramic)

Quartz Sandstone

Quartz Arenite

Iron-rich sandstone or weathered ironstone

Ferruginous sandstone; predominantly quartz (SiO₂) cemented or stained by iron oxides such as hematite and goethite

Polished blue calcite sphere (tentative identification)

Calcite, CaCO₃; blue color generally results from trace impurities or inclusions

Man-made Carved Stone (Scream Mask/Skull motif)

Carved Soapstone or Serpentine-rich rock

Fossiliferous Limestone

Limestone (CaCO3 - Calcium Carbonate)

Mica-rich Sandstone or Micaceous Schist Weathering

Micaceous Schist (Muscovite-Quartz composition)

Coal (Anthracite or Bituminous)

Lithified plant matter (Carbon)

Fossilized Coprolite

Coprolite (fossilized feces)

Fossiliferous Chert or Limestone

Sedimentary rock containing fossilized marine invertebrates (likely crinoid stems or bryozoans)

Sandstone

Clastic sedimentary rock (primarily SiO2)

Sandstone (Red Sandstone)

Arenite (SiO2 based with Fe2O3 staining)

River Cobble (Quartzite or Sandstone)

Arenite or Meta-quartzite (SiO2 composition)

Fossilized Rugose Coral

Order Rugosa (Calcium Carbonate - CaCO3)

Sandstone (Quartzite texture)

Arenite (SiO2 secondary)

Calcite-rich limestone, possibly fossiliferous

Limestone composed mainly of calcite (CaCO₃), potentially containing a fragmentary fossil or calcite-filled structure

Fossiliferous Limestone (Pink/Red)

Calcium Carbonate (CaCO3) with Bioclasts

Polished fossiliferous limestone, likely crinoidal or coral limestone

Calcite (CaCO₃), fossiliferous carbonate rock

Green Sea Glass

Amorphous Silica (man-made glass), SiO2 + additive metal oxides

Slate

Slate (foliated metamorphic rock)

Sandstone (likely Arkosic)

Clastic Sedimentary Rock (primarily SiO2 with Feldspar)

Siltstone or Mudstone

Siltstone (composed primarily of silt-sized particles)

Goldstone (aventurine glass)

Man-made copper-bearing glass; not a natural mineral (commonly sold as blue/brown goldstone)

Tumbled tan pebble, likely sandstone or chert

Uncertain; probable quartz-rich sandstone (SiO₂-bearing)

Sandstone (Ferruginous)

Arenite (primarily SiO2 with iron oxide cement)

Conglomerate

Clastic Sedimentary Rock (Conglomerate)

Man-made Glass (Tumbled/Shaped)

Amorphous Silicon Dioxide (SiO2) with metal oxide colorants

Man-made Slag (Industrial Byproduct)

Anthropogenic Glassy Residue

Man-made Crystal (Lead Glass)

Lead oxide-doped Silica Glass (approx. SiO2 + PbO)