Industrial Byproduct (Anthropogenic Rock Like Material)

Opalite-style glass pendant

Man-made opalescent glass (not natural opal)

Granodiorite (containing Biotite and Quartz)

Granodiorite (Plagioclase-rich phaneritic intrusive rock)

Rounded pale pebble, likely quartz-rich stone

Indeterminate; possibly quartzite, quartz-bearing granite, or calcite-rich limestone

Quartz-rich pegmatitic rock with possible epidote or chlorite

Hydrothermal/pegmatitic quartz-bearing rock; identifiable minerals may include quartz (SiO₂), feldspar, and epidote/chlorite

Serpentine

Antigorite/Chrysotile/Lizardite (Mg,Fe)3Si2O5(OH)4

Basalt

Basalt (Aphanitic Mafic Volcanic Rock)

Unidentified gray metallic object

Not determinable from the image; likely a metal screw or manufactured fastener rather than geological material

Chert (Arrowhead/Projectile Point)

Microcrystalline quartz (SiO2)

Chert (often called Flint)

Chert (Microcrystalline Quartz, SiO2)

Yellow Calcite

Calcium Carbonate (CaCO3)

Chert Arrowhead

Microcrystalline Quartz (SiO2)

Blue slag-like mineral specimen, possibly bornite or chalcopyrite

Tentatively bornite (Cu5FeS4) or iridescent chalcopyrite (CuFeS2)

Polished agate-like stone (uncertain; possibly a fossil or shell fragment)

Likely microcrystalline quartz (chalcedony), SiO₂; exact identification is limited by the image

Quartz-rich breccia or silicified rock

Microcrystalline quartz (SiO₂), with iron-oxide staining and possible feldspar/calcite fragments

Chert (Arrowhead Debitage or Flake)

Microcrystalline silica (SiO2)

Botryoidal prehnite

Prehnite, Ca₂Al(AlSi₃O₁₀)(OH)₂

Iron-stained Quartz Vein

Silicon Dioxide (SiO2) with Limonite/Hematite inclusions

Chert (Arrowhead Fragment)

Microcrystalline Quartz (SiO2)

Polished tiger’s-eye (likely iron-rich quartzite)

Quartzite composed mainly of SiO₂, with fibrous crocidolite pseudomorphs oxidized to iron oxides

Grooved Maun Ball (Maul/Hammerstone-like Concretion)

Calcareous/Ferruginous Concretion in Sandstone Matrix

Chalcanthite

Hydrated copper(II) sulfate (CuSO4·5H2O)

Ferruginous Sandstone

Clastic Sedimentary Rock (Sandstone with Iron Oxide cement)

Chert (Arrowhead)

Microcrystalline Quartz (SiO2)

Sandstone (Quartz-rich)

Clastic sedimentary rock (SiO2 primary)

Possible fossilized shell or fossil fragment

Indeterminate; possibly a small brachiopod or gastropod fossil in mineralized matrix

Green Sea Glass

Man-made vitreous material (silica glass)

Bauxite

Bauxite (Mixture of Al(OH)3, AlO(OH), and Fe2O3)

Mystic Topaz

Aluminum silicate fluoride hydroxide with titanium coating (Al2SiO4(F,OH)2)

Brecciated jasper (likely ocean jasper or rhyolitic jasper)

Silica-rich volcanic breccia composed mainly of microcrystalline quartz/chalcedony (SiO₂), with iron-oxide staining and possible feldspar

Basalt

Basalt (Mafic volcanic rock)

Sandstone (Red/Brown Variety)

Arenite (composed primarily of SiO2 with Fe2O3 iron oxide inclusions)

Milky quartz in dark host rock

Quartz (SiO₂), likely as a vein or vein fragment; host rock uncertain

Red Sandstone

Arenite (with Iron Oxide / Hematite cementation)

Possible basalt or iron-rich slag-like geological specimen

Basalt (tentative); predominantly plagioclase and pyroxene, possibly with magnetite/iron oxides

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Pumice (specifically a water-worn, weathered variety)

Vesicular volcanic glass

Iron meteorite fragment

Fe-Ni meteorite, likely an iron meteorite or stony-iron fragment

Sea Glass

Man-made silicate glass weathering product

Basalt

Basalt (Mafic Extrusive Igneous Rock)

Small gray rock fragment

Indeterminate; possibly quartz-rich granite, chert, or concrete-like silicate material

Quartz Pebble

Silicon Dioxide (SiO2)

Ironstone (likely Limonite or Goethite)

Ferruginous sedimentary rock (FeO(OH)·nH2O)