Mineraloid (Human Made Geological Specimen)

Chert (Flint)

Silicon Dioxide (SiO2)

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

Carved Soapstone or Serpentine-rich rock

Carved quartz skull, likely smoky quartz or gray chalcedony

Silicon dioxide (SiO₂), quartz or microcrystalline quartz

Iridescent bismuth crystal

Bismuth (Bi), artificially crystallized

Chert (flint), brown variety

Microcrystalline quartz (SiO₂)

Red-and-brown agate bead bracelet

Agate, a microcrystalline variety of quartz (SiO₂), likely colored chalcedony/carnelian

Cobalt Glass Slug (Man-made Glass)

Amorphous Silica with Cobalt Oxide (SiO2 + CoO)

Milky quartz

Quartz (silicon dioxide, SiO₂)

Bismuth Crystal

Bismuth (Bi)

Concretion with Geode Cavity

Ferruginous Sandstone Concretion with Quartz Center

Chert

Microcrystalline quartz (SiO2)

Painted Sandstone

Sandstone (clastic sedimentary rock) with acrylic/artistic coating

Obsidian (likely black volcanic glass)

Obsidian; primarily amorphous volcanic silica glass, approximately SiO₂-rich rhyolitic composition

Likely chert (flint)

Microcrystalline quartz (SiO₂), likely chert; exact identification is uncertain from the image alone

Gem-set gold ring

Likely a faceted diamond (carbon, C) set in a gold-alloy ring; the surrounding stones are not identifiable from the image.

Possible weathered metal-rich rock or slag fragment

Uncertain; possibly iron-oxide-rich breccia or industrial slag

Flint (chert)

Microcrystalline quartz (SiO₂), a variety of chert

Tumbled cream-colored pebble, likely quartz or calcite

Indeterminate from photograph; possibilities include microcrystalline quartz (SiO₂) or calcite (CaCO₃)

Chert / Flint (Arrowhead Artifact)

Microcrystalline quartz (SiO2)

Small rounded pebble (rock type indeterminate)

Unidentified fine-grained lithic pebble

Tumbled greenstone / serpentinite (probable)

Serpentinite, chiefly Mg-rich serpentine minerals (antigorite, lizardite, chrysotile), possibly mixed with chlorite, magnetite, or carbonate

Conglomerate

Clastic Sedimentary Rock (Conglomerate)

Polished agate or chalcedony pebble

Microcrystalline quartz, SiO₂ (chalcedony; exact identification uncertain from the image)

Chert / Flint

Microcrystalline Quartz (SiO2)

Chert (often called Flint)

Chert (Cryptocrystalline Quartz, SiO2)

Hand-Drawn Gengar Pokémon Card Artist Item

Lignocellulosic Fiber (Cellulose, C6H10O5) with wax-based pigment (crayon/colored pencil)

Obsidian

Obsidian (volcanic glass)

Tumbled green fluorite (probable)

Fluorite, calcium fluoride (CaF₂)

Faceted blue gemstone ring, likely synthetic spinel or glass; identity uncertain

Possibly synthetic blue spinel (MgAl₂O₄) or laboratory sapphire (Al₂O₃); the clear side stones may be cubic zirconia or glass

Goldstone

Aventurine Glass (Man-made glass with copper inclusions)

Asphalt Concrete (Bituminous Conglomerate)

Anthropogenic Bituminous Conglomerate

Chert Nodule

Microcrystalline Quartz

Chert (often called Flint or Jasper if reddish)

Microcrystalline Quartz (SiO2)

Opalite

Synthetic Glass (Simulated Opal)

Snowflake Obsidian

Spherulitic Obsidian (Volcanic Glass with Cristobalite inclusions)

Black Pearl (Tahitian Pearl)

Aragonite / Calcite (CaCO3) with Conchiolin

Polished pink feldspar (likely moonstone/sunstone-type feldspar)

Alkali feldspar, commonly orthoclase or microcline; KAlSi₃O₈

Lava Rock with Fabric Impression

Scoria or Basalt with anthropogenic impressions

Tumbled blue glassy mineral specimen, possibly blue calcite or dyed quartz

Uncertain from image; likely calcite (CaCO₃) or dyed microcrystalline quartz (SiO₂)

Tumbled chalcedony (likely moss or dendritic agate)

Microcrystalline quartz, SiO₂, with iron-oxide inclusions

Possible ironstone concretion or weathered mineral nodule

Iron-oxide-rich concretion, likely goethite/limonite; identification uncertain from the photo

Dark blue polished stone pendant

Indeterminate; possibly sodalite, lapis lazuli, or blue slag/glass-like material