None

Chert / Jasper

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Obsidian

Volcanic Glass (SiO2 - Silicon Dioxide with impurities)

Sandstone Concretion

Clastic sedimentary rock (primarily Quartz SiO2)

Black Obsidian

Obsidian (Volcanic Glass, SiO2 + impurities)

Fossiliferous Limestone

Bioclastic Limestone (CaCO3)

Weathered limestone

Calcite-rich carbonate rock; primarily CaCO₃

Basalt

Basalt; fine-grained mafic volcanic rock composed mainly of plagioclase, pyroxene, and commonly olivine

Likely basalt (possibly iron-rich volcanic rock)

Basalt; predominantly plagioclase feldspar, pyroxene, and commonly olivine or iron oxides

Tumbled black stone, likely obsidian

Volcanic glass; chiefly amorphous silica (SiO₂)

Weathered limestone

Calcite-rich carbonate rock (mostly CaCO₃)

Tumbled dark stone, likely basalt

Basalt (fine-grained mafic volcanic rock; commonly plagioclase, pyroxene, and minor olivine)

Shungite

Non-crystalline carbon (C)

Agate

Silicon Dioxide (SiO2)

Note: Item is not a geological specimen

Homo sapiens (Dermal Appendage: Pilus)

Obsidian

Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)

Shungite

Shungite (Non-crystalline carbon, C)

Decorative gemstone bracelet or jewelry

Unidentifiable from the blurred image; likely colored glass or synthetic stones, possibly mixed gemstone beads

Native Gold

Gold (Au)

Likely basalt

Basalt, a fine-grained mafic volcanic rock composed mainly of plagioclase feldspar and pyroxene, commonly with olivine

Likely metallic meteorite fragment

Undetermined iron or stony-iron meteorite; mineralogy requires testing

Weathered light-colored stone, likely limestone

Calcitic limestone; predominantly calcium carbonate (CaCO₃), possibly chalky or dolomitic

Chert (River Pebble)

Chert (Cryptocrystalline Quartz, SiO₂)

Weathered basalt cobble

Basalt; chiefly plagioclase feldspar, clinopyroxene, and commonly olivine or magnetite

Red sandstone fragment

Ferruginous sandstone, chiefly quartz (SiO₂) with iron-oxide cement

Dark basalt cobble

Basalt, predominantly plagioclase and pyroxene with possible olivine

Likely basalt

Basalt; fine-grained mafic volcanic rock, chiefly plagioclase and pyroxene with possible olivine

Dark volcanic pebble, likely basalt

Basalt; fine-grained mafic rock composed mainly of plagioclase, pyroxene, and commonly olivine or magnetite

Chert Concretion

Sedimentary Cryptocrystalline Quartz (SiO2)

Lepidodendron Fossil in Sandstone

Lepidodendron (Lycophytina, Lepidodendrales)

Amber

Succinite (fossilized tree resin)

Siltstone

Siltstone (primarily SiO2 with Al2O3)

Agate

Silicon Dioxide (SiO2)

Gold Nugget

Native Gold (Au)

Chert (Nodule)

Chert (Silicon dioxide, SiO2)

Quartz-rich sandstone or quartzite pebble

Sandstone, likely arkosic or quartzose; possibly weakly metamorphosed quartzite

Weathered quartz-rich rock, likely milky quartz/quartzite

Quartz (SiO₂), possibly quartzite with minor iron-oxide staining

Flint (Chert Node)

Silicon Dioxide (SiO2)

Fossilized Oyster Shell

Ostreidae (Calcium Carbonate - CaCO3)

Dyed Agate Geode

Silicon Dioxide (SiO2) - Chalcedony variety

Obsidian

Volcanic Glass (SiO2 + minor impurities)

Chert (Jasper/Flint Pebble)

Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)

Chalcedony (Agate/Common Opal blend)

Microcrystalline Quartz (SiO2)