Biogenic Material

Flint

SiO2 (Microcrystalline Quartz / Chert)

Chert (often called Flint in archaeological contexts)

Microcrystalline or cryptocrystalline Silica (SiO2)

Chert / Jasper

Silicon Dioxide (SiO2)

Chert (Nodule)

Microcrystalline Quartz (SiO2)

Chert (River Pebble)

Microcrystalline silica (SiO2)

Chert

Chert (SiO2)

Painted Pet Rock (Quartzite/Sandstone base)

Silicon Dioxide (SiO2) with anthropomorphic acrylic embellishments

Chert (specifically Red Chert/Jasper)

Microcrystalline Quartz (SiO2)

Chert (Red Jasper variant)

Microcrystalline Quartz (SiO2)

Green aventurine beads

Quartz (SiO₂), typically green quartzite/aventurine with fuchsite mica inclusions

Fossilized Bone

Permineralized Vertebrate Bone

Chert

Microcrystalline Quartz (SiO2)

Ferruginous Quartz

Iron-stained Quartz (Silicon Dioxide, SiO2 with Fe2O3 inclusions)

Asphalt (Bituminous Concrete)

Bituminous mix containing aggregates and petroleum-based binder (CnH2n+2)

Chert / Jasper

Silicon Dioxide (SiO₂)

Red Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Iron-rich laterite or limonite/goethite-bearing rock

Hydrated iron oxides, chiefly goethite (α-FeO(OH)) and limonite (FeO(OH)·nH₂O), likely in a lateritic matrix

Iron-rich weathered rock, likely limonite/goethite-bearing laterite

Limonite (variable hydrated iron oxides; chiefly goethite, α-FeO(OH))

Milky quartz–rich rock

Quartz (SiO₂), likely massive milky quartz with minor dark inclusions

Polished orbicular stone, likely granite or diorite

Granite–diorite, composed mainly of feldspar, quartz, and dark amphibole/biotite

Iron-stained quartz-rich rock, possibly jasper/quartzite

Quartz (SiO₂) with iron-oxide staining; likely ferruginous quartzite or jasper

Tumbled chalcedony (likely brown agate/jasper)

Microcrystalline quartz, SiO₂; potentially iron-stained chalcedony or jasper

Tumbled jasper or quartzite pebble

Jasper (microcrystalline quartz, SiO₂), possibly iron-stained quartzite

Iron-stained garnet-bearing rock, possibly almandine garnet

Garnet-group silicate, likely almandine (Fe₃Al₂Si₃O₁₂), in a quartz–iron-oxide matrix

Asphalt aggregate (crushed stone in bitumen)

Artificial composite; predominantly crushed granite, basalt, limestone, and/or recycled aggregate bound by bitumen

Weathered quartz-rich sandstone or granitic rock

Indeterminate; likely iron-stained quartz sandstone, possibly weathered granite

Conical fossil shell or shell fragment

Likely a gastropod shell fragment; exact taxon indeterminate from the image

Tumbled granite or granitic gneiss

Granite, typically quartz + feldspar + mica; possibly foliated granitic gneiss

Mammoth or Mastodon Tooth Fossil

Proboscidea tooth (Mammuthus or Mammut)

Chert (varieties include Flint and Jasper)

Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)

Terrazzo (with Marble and Granite fragments)

Cementitious or resinous composite containing Calcium Carbonate (CaCO3) and Silicates

Chert (Quartz Variety)

Silicon Dioxide (SiO2)

Carnelian

Chalcedony (cryptocrystalline quartz), SiO2

Lava Rock (Basalt)

Basalt (extrusive igneous rock)

Tumbled greenstone, likely nephrite jade

Nephrite jade (interlocking tremolite–actinolite amphibole; Ca₂(Mg,Fe)₅Si₈O₂₂(OH)₂)

Red Sandstone

Arenite (Ferruginous Sandstone)

Polished orbicular jasper

Silica-rich microcrystalline quartz/chalcedony (SiO₂), with iron oxides and green alteration minerals

Iron-rich quartzite or ironstone

Ferruginous quartzite; predominantly quartz (SiO₂) with hematite/goethite (Fe₂O₃/FeO(OH))

Polished orange agate/jasper cabochon

Microcrystalline quartz (chalcedony), SiO₂, with iron-oxide coloration; exact variety uncertain

Polished green aventurine

Quartzite dominated by quartz (SiO₂), with green fuchsite mica or chlorite inclusions

Dark basalt or basaltic volcanic rock

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

Orbicular jasper (likely ocean jasper)

Silica-rich microcrystalline quartz/chalcedony with feldspar and accessory minerals; composition varies