Rock Identifier

Category

Artifact

Browse artifact specimens identified by the Rock Identifier community.

Flint (chert) flake/tool (Microcrystalline quartz (SiO₂), likely brown flint/chert) — sedimentary

Flint (chert) flake/tool

Microcrystalline quartz (SiO₂), likely brown flint/chert

Red jasper flake/tool blank (Jasper, microcrystalline quartz (SiO₂), colored by iron oxides) — mineral

Red jasper flake/tool blank

Jasper, microcrystalline quartz (SiO₂), colored by iron oxides

Chert (Flint) (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Flint)

Cryptocrystalline Quartz (SiO2)

Flaked stone projectile point (Likely worked chert or fine-grained silicified shale; exact lithology cannot be confirmed from the image) — metamorphic

Flaked stone projectile point

Likely worked chert or fine-grained silicified shale; exact lithology cannot be confirmed from the image

Weathered flint or chert nodule (Microcrystalline quartz (SiO₂), commonly flint/chert) — sedimentary

Weathered flint or chert nodule

Microcrystalline quartz (SiO₂), commonly flint/chert

Obsidian (Obsidian (Volcanic Glass)) — igneous

Obsidian

Obsidian (Volcanic Glass)

Gray flint or chert fragment (Microcrystalline quartz (SiO₂), likely chert/flint) — sedimentary

Gray flint or chert fragment

Microcrystalline quartz (SiO₂), likely chert/flint

Quartzite (Quartzite (primarily Silicon Dioxide, SiO2)) — metamorphic

Quartzite

Quartzite (primarily Silicon Dioxide, SiO2)

Chert (specifically Flint or Jasper variant) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Flint or Jasper variant)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Arrowhead Debitage or Flake) (Microcrystalline silica (SiO2)) — sedimentary

Chert (Arrowhead Debitage or Flake)

Microcrystalline silica (SiO2)

Worked chert (likely flint) (Microcrystalline quartz/chalcedony, SiO₂) — sedimentary

Worked chert (likely flint)

Microcrystalline quartz/chalcedony, SiO₂

Chert Nodule (Commonly known as a Flint or River Cobble) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert Nodule (Commonly known as a Flint or River Cobble)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Chert

Microcrystalline Quartz (SiO2)

Chert / Flint Pebble (Silicon Dioxide (SiO2)) — sedimentary

Chert / Flint Pebble

Silicon Dioxide (SiO2)

Chert (Flint) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Flint)

Microcrystalline Quartz (SiO2)

Flint or chert flake/tool (Microcrystalline quartz (chalcedony), SiO₂) — sedimentary

Flint or chert flake/tool

Microcrystalline quartz (chalcedony), SiO₂

Flint or chert fragment (Microcrystalline quartz (SiO₂), likely flint/chert) — sedimentary

Flint or chert fragment

Microcrystalline quartz (SiO₂), likely flint/chert

Flint or chert flake (Microcrystalline quartz (SiO₂), commonly chalcedony with possible minor impurities) — sedimentary

Flint or chert flake

Microcrystalline quartz (SiO₂), commonly chalcedony with possible minor impurities

Obsidian (Arrowhead Lithic Tool) (Obsidian (Amorphous Volcanic Glass / SiO2 + inclusions)) — igneous

Obsidian (Arrowhead Lithic Tool)

Obsidian (Amorphous Volcanic Glass / SiO2 + inclusions)

Chert or flint cobbles (Microcrystalline quartz (SiO₂), commonly with chalcedony) — sedimentary

Chert or flint cobbles

Microcrystalline quartz (SiO₂), commonly with chalcedony

Chert (Arrowhead Fragment) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Arrowhead Fragment)

Microcrystalline Quartz (SiO2)

Jasper / Flint / Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Jasper / Flint / Chert

Microcrystalline Quartz (SiO2)

Gray flint/chert flake or tool (Microcrystalline quartz (SiO₂), commonly chalcedony) — sedimentary

Gray flint/chert flake or tool

Microcrystalline quartz (SiO₂), commonly chalcedony

Dark fine-grained stone, likely basalt (Basalt; chiefly plagioclase feldspar and pyroxene, commonly with minor olivine and iron oxides) — igneous

Dark fine-grained stone, likely basalt

Basalt; chiefly plagioclase feldspar and pyroxene, commonly with minor olivine and iron oxides

Polished black stone, possibly basalt or black obsidian (Likely fine-grained basalt (plagioclase and pyroxene) or volcanic glass (obsidian; rhyolitic composition)) — igneous

Polished black stone, possibly basalt or black obsidian

Likely fine-grained basalt (plagioclase and pyroxene) or volcanic glass (obsidian; rhyolitic composition)

Chert (specifically Flint or Dark Chert) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (specifically Flint or Dark Chert)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chert (Tan/Buff Chert) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Tan/Buff Chert)

Microcrystalline Quartz (SiO2)

Chert (or potentially massive Quartz/Quartzite) (SiO2 (Silicon Dioxide)) — sedimentary (if chert) / metamorphic (if quartzite)

Chert (or potentially massive Quartz/Quartzite)

SiO2 (Silicon Dioxide)

sedimentary (if chert) / metamorphic (if quartzite)

Sandstone (Ferruginous) (Sandstone (SiO2 with iron oxide impurities)) — sedimentary

Sandstone (Ferruginous)

Sandstone (SiO2 with iron oxide impurities)

Flint or chert knapped tool/flake (Microcrystalline quartz (SiO₂), likely chert/flint) — sedimentary

Flint or chert knapped tool/flake

Microcrystalline quartz (SiO₂), likely chert/flint

Native American Hammerstone / Pitted Stone (Modified lithic artifact (often quartzite, basalt, or granite)) — artifact / sedimentary or igneous rock

Native American Hammerstone / Pitted Stone

Modified lithic artifact (often quartzite, basalt, or granite)

artifact / sedimentary or igneous rock

Chert or flint fragment (Microcrystalline quartz (SiO₂), commonly chalcedony with cryptocrystalline quartz) — sedimentary

Chert or flint fragment

Microcrystalline quartz (SiO₂), commonly chalcedony with cryptocrystalline quartz

Chert (often called Flint) (Chert (Microcrystalline Quartz, SiO2)) — sedimentary

Chert (often called Flint)

Chert (Microcrystalline Quartz, SiO2)

Chert (Chalcedony/Agate variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Chalcedony/Agate variety)

Microcrystalline Quartz (SiO2)

Chert (Flint Nobule) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Flint Nobule)

Silicon Dioxide (SiO2)

Chert (Flint) (Chert (Microcrystalline or cryptocrystalline Quartz, SiO2)) — sedimentary

Chert (Flint)

Chert (Microcrystalline or cryptocrystalline Quartz, SiO2)

Chert (Iron-Stained) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Iron-Stained)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Greenstone / altered mafic rock (Likely chlorite–actinolite schist or metabasalt; exact identification requires testing) — metamorphic

Greenstone / altered mafic rock

Likely chlorite–actinolite schist or metabasalt; exact identification requires testing

Flint or chert, possibly a knapped stone tool (Microcrystalline quartz (SiO₂), commonly chalcedony with possible carbonaceous impurities) — sedimentary

Flint or chert, possibly a knapped stone tool

Microcrystalline quartz (SiO₂), commonly chalcedony with possible carbonaceous impurities

Weathered chert or novaculite (flaked stone tool/fragment possible) (Microcrystalline quartz (SiO₂); likely chert, possibly Arkansas novaculite) — sedimentary

Weathered chert or novaculite (flaked stone tool/fragment possible)

Microcrystalline quartz (SiO₂); likely chert, possibly Arkansas novaculite

Basalt Arrowhead (worked stone) (Aphanitic mafic volcanic rock (Basalt)) — igneous

Basalt Arrowhead (worked stone)

Aphanitic mafic volcanic rock (Basalt)

Chert (Arrowhead/Artifact Fragment) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Arrowhead/Artifact Fragment)

Microcrystalline or Cryptocrystalline Quartz (SiO2)