Man Made Material

Chert (Flint)

Chert (Microcrystalline Quartz, SiO2)

Clear quartz sphere

Quartz (silicon dioxide, SiO₂), likely rock crystal or low-grade milky quartz

Likely iron-rich slag or weathered ironstone

Hematite–goethite-rich material (Fe₂O₃/FeO(OH)); possibly industrial iron slag

Quartz Pebble

Silicon Dioxide (SiO2)

Sandstone (Quartzose Sandstone)

Clastic Sedimentary Rock (primarily SiO2)

Quartz-rich rock, possibly milky quartz or quartzite

Quartz (SiO₂), potentially quartzite if the grains are fused

Iron-rich chert or jasper

Microcrystalline quartz (SiO₂), colored by hematite/goethite inclusions

Scoria

Scoria (a vesicular basalt or andesite)

Fossilized tooth, likely mammalian molar

Indeterminate Mammalia; mineralized dentine and enamel

Granite

Intrusive igneous rock composed mainly of quartz, alkali feldspar, and plagioclase

Blue Apatite

Fluorapatite (Ca5(PO4)3F)

Green Banded Chert (Agate/Jasper)

Silicon Dioxide (SiO2) with trace impurities of Chlorite or Glauconite

Tumbled banded jasper, likely brecciated jasper

Microcrystalline quartz (SiO₂) with iron-oxide and clay inclusions

Chert (Flint)

Chert (predominantly SiO₂ - silicon dioxide)

Diamond (or diamond simulant)

C

Pink-and-white quartz-rich rock, likely rose quartz matrix

Quartz (SiO₂), possibly intergrown with feldspar or chalcedony

Rounded gray pebble, likely basalt or andesite

Fine-grained volcanic rock, probably basaltic-andesite; exact identification requires testing

Quartz-rich metamorphic rock, likely quartzite

Quartzite; predominantly microcrystalline quartz (SiO₂), possibly with mica or feldspar

Tumbled white quartz or quartzite pebble

Quartz (SiO₂), possibly massive quartzite

Diamond (or Cubic Zirconia)

Cubic Carbon (C) or Zirconium Dioxide (ZrO2)

Sandstone (Quartzose)

Arenite (composed primarily of SiO2)

Sandstone

Arenite (SiO2 primarily)

Yellow-orange faceted gemstone, likely citrine or yellow topaz

Citrine: quartz, SiO₂; yellow topaz: Al₂SiO₄(F,OH)₂

Weathered quartz-rich rock, possibly chert or milky quartz

Mostly microcrystalline or crystalline quartz (SiO₂), identification uncertain from photograph

Tumbled dark gray stone, likely basalt

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

Diamond (in Matrix)

Carbon (C)

Polished red jasper

Jasper, an opaque microcrystalline variety of quartz (SiO₂), colored mainly by iron oxides

Chert

Chert (Microcrystalline Silica, SiO2)

Chert (Flint)

Microcrystalline Quartz (SiO2)

Banded Chert

Microcrystalline Quartz (SiO2)

Quartz-rich pebble, possibly chert or silicified limestone

Microcrystalline quartz (SiO₂), possibly chalcedony; exact identification is uncertain from the photograph

Tumbled orange chalcedony (likely carnelian)

Microcrystalline quartz, SiO₂; iron-bearing variety commonly termed carnelian

Carnelian/chalcedony rough

Microcrystalline quartz (SiO₂), iron-oxide-colored chalcedony

Weathered quartz-rich stone, possibly fossiliferous limestone

Indeterminate; likely calcite-rich limestone (CaCO₃) or weathered quartz-bearing rock

Chert (Flint)

Silicon Dioxide (SiO2)

Chert (Flint Nodules)

Silicon Dioxide (SiO2)

Chert (Flint)

Chert (SiO2)

Chert (varietal Flint)

Chert (SiO2)

Chert

Microcrystalline silica (SiO2)

Sandstone

Clastic Sedimentary Rock

Sandstone

Arenite (Sandstone)

Sandstone

Arenite