Artifact

Volcanic Scoria (Metate)

Vesicular Basalt

Chert (specifically as a lithic artifact/projectile point)

Chert (Silicon dioxide, SiO2)

Chert (specifically Flint Arrowhead)

Silicon dioxide (SiO2) - Microcrystalline Quartz

Chert or silicified sedimentary fragment (tentative)

Microcrystalline quartz (SiO₂), possibly silicified limestone or fossil-bearing chert

Weathered sandstone or fine-grained sedimentary rock

Quartz-rich sandstone, possibly arkose or lithic sandstone

Chert (flint), likely a knapped piece

Microcrystalline quartz (SiO₂), commonly called chert or flint

Obsidian (likely Apache tear or flaked obsidian)

Volcanic glass; primarily rhyolitic silica glass (SiO₂-rich, non-crystalline)

Fired Clay Brick (Anthropic Rock substitute)

Anthropogenic polycrystalline ceramic (predominantly Mullite and Quartz: Al6Si2O13 + SiO2)

Sandstone (Grooved/Weathered)

Arenite (composed primarily of Quartz and Lithic fragments)

Chert Nodules in Limestone

Microcrystalline Quartz (SiO2) within Calcium Carbonate (CaCO3)

Chert (Flint)

Microcrystalline Quartz (SiO2)

Chert

Microcrystalline Quartz (SiO2)

Chert or flint fragment

Microcrystalline quartz (SiO₂), possibly iron-stained chert

Chert (flint), likely with iron-stained weathering rind

Microcrystalline quartz/chalcedony (SiO₂)

Chert (Field-collected Arrowhead-shaped Fragment)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (often called Flint or Jasper when red)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chert (Nodule)

Chert (Silicon Dioxide, SiO2)

Chert (often called Flint when dark)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (often found as Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Flint (chert) flake/tool

Microcrystalline quartz (SiO₂), likely brown flint/chert

Red jasper flake/tool blank

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

Flint or chert flake/tool

Microcrystalline quartz (chalcedony), SiO₂

Likely banded chert (flint) fragment

Microcrystalline quartz, SiO₂; visual identification is uncertain from the image alone

Weathered flint or chert nodule

Microcrystalline quartz (SiO₂), commonly flint/chert

Obsidian

Obsidian (Volcanic Glass)

Gray flint or chert fragment

Microcrystalline quartz (SiO₂), likely chert/flint

Quartzite

Quartzite (primarily Silicon Dioxide, SiO2)

Chert (specifically Flint or Jasper variant)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Arrowhead Debitage or Flake)

Microcrystalline silica (SiO2)

Worked chert (likely flint)

Microcrystalline quartz/chalcedony, SiO₂

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

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert

Microcrystalline Quartz (SiO2)

Chert / Flint Pebble

Silicon Dioxide (SiO2)

Chert (Flint)

Microcrystalline Quartz (SiO2)

Chert (Arrowhead variety)

Chert (SiO2)

Flint or chert fragment

Microcrystalline quartz (SiO₂), likely flint/chert

Chert (Flint)

Cryptocrystalline Quartz (SiO2)

Flint or chert flake

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

Flaked stone projectile point

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

Chert or flint cobbles

Microcrystalline quartz (SiO₂), commonly with chalcedony

Native American Hammerstone / Pitted Stone

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

Obsidian (Arrowhead Lithic Tool)

Obsidian (Amorphous Volcanic Glass / SiO2 + inclusions)