Mineral (Man Made Composite)

Chalcedony (likely blue agate) knapped into an arrowhead

Microcrystalline quartz, SiO₂ (chalcedony)

Quartz Sandstone Pebble

Sandstone (SiO2 dominated)

Aura Quartz (Anomalously Coated Quartz)

Silicon Dioxide (SiO2) treated with vaporized metals

Sandstone

Arenite

Sandstone

Arenite (mostly SiO2)

Polished yellow calcite

Calcite (calcium carbonate, CaCO₃)

Chalcedony (Agate / Jasper Specimen)

Silicon Dioxide (SiO2)

Diamond (in Jewelry)

Carbon (C)

Vesicular Basalt (or Scoria)

Vesicular Basalt

Sandstone

Arenite (composed primarily of SiO2)

Granite

Granite (a plutonic igneous rock)

Chalcedony / milky quartz flake

Microcrystalline quartz (SiO₂), likely chalcedony; possibly a worked quartzite or chert fragment

Green iridescent glass cabochon or synthetic gemstone

Likely synthetic glass; possibly coated synthetic quartz or lab-created green gemstone

Polished orbicular jasper (likely ocean jasper)

Siliceous microcrystalline quartz/chalcedony with iron-oxide and volcanic inclusions; commonly called ocean jasper

Tumbled quartz-rich pebble

Microcrystalline quartz (SiO₂), possibly milky quartz or quartzite

Red glass-like crystal, likely synthetic ruby or red glass

Uncertain from image; possible corundum (ruby), Al₂O₃, or synthetic glass

Sandstone

Arenite (composed primarily of SiO2)

Corundum (Sapphire variant)

Aluminium oxide (Al2O3)

Chrysocolla

Hydrated copper phyllosilicate, (Cu,Al)2H2Si2O5(OH)4·nH2O

Diamond

Carbon (C)

Diamond

Carbon (C)

Sandstone

Sedimentary Rock (Quartz Sandstone)

Conglomeratic concrete or asphalt aggregate surface with dark bituminous chunks

Polymictic gravel aggregate; dark pieces likely bitumen/asphalt, not a natural rock

Diamond (faceted)

Diamond (Pure Carbon, C)

Pearl

Aragonite (CaCO3) with Conchiolin

Aragonite

Aragonite (Calcium Carbonate - CaCO3)

Sandstone

Sandstone (composed predominantly of Quartz, SiO2, with Feldspar and Clay minerals)

Turquoise

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

Pyrite

Iron Sulfide (FeS2)

Granite

Granite (Phaneritic Quartz-Feldspar intrusive rock)

Sandstone

Arenite (SiO2 based)

Sandstone

Arenite (SiO2 based clastic rock)

Fossil or modern bivalve shell

Calcium carbonate shell, likely aragonite (CaCO₃); exact species cannot be determined from the image

Pale green aventurine (likely quartz) sphere

Quartz, SiO₂; possibly pale green aventurine, with color from inclusions or treatment

Sandstone

Arenite (primarily SiO2)

Sandstone

Arenite

Trilobite fossil

Trilobita (exact species indeterminable from the image)

Tumbled blue-green stone, likely chrysocolla or dyed chalcedony

Probable chrysocolla (hydrated copper aluminosilicate; variable composition), though appearance could also represent dyed chalcedony

Unidentified gray stone/concrete-like fragment

Indeterminate; likely a fine-grained carbonate or cementitious geological fragment

Polished black stone pendant

Likely black obsidian or black tourmaline; exact identification is uncertain from the photograph

Yellow Quartz Pebble

Silicon Dioxide (SiO2)

Smoky Quartz

Smoky Quartz (SiO2)