Industrial Byproduct (Anthropogenic Rock Like Material)

Basalt

Basalt (Mafic volcanic rock)

Fluorite (Fluor-spar)

Calcium Fluoride (CaF2)

Serpentine / Serpentinite (with Weathering Crust)

Serpentinite (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4

River Siltstone / Mudstone Pebble

Siltstone (composed of mixed silicate and carbonate minerals)

Note: Item is not a geological specimen

Polyester mesh and Ethylene-vinyl acetate (EVA) polymer

Amethyst cluster

Amethyst, purple quartz (SiO₂)

Granodiorite Pebble

Granodiorite

Bauxite

Aluminum ore (mixture of gibbsite Al(OH)3, boehmite γ-AlO(OH), and diaspore α-AlO(OH))

Blue Dyed Quartzite

Silicon Dioxide (SiO2) with artificial pigment

Sandstone

Arenite (primarily SiO2)

Possible iron-rich chert or slag-like rock

Microcrystalline quartz (SiO₂), possibly iron-stained chert; exact identification is uncertain from the image

Iron-stained quartz-rich cobble, possibly weathered granite or quartz vein rock

Quartz–feldspar aggregate with iron-oxide staining; exact classification is uncertain from the photograph

Peridot (Olivine)

Olivine ((Mg, Fe)2SiO4)

Chert (Arrowhead or Flake)

Microcrystalline quartz (SiO2)

Chert Arrowhead

Microcrystalline Quartz (SiO2)

Banded Chert

Microcrystalline Quartz (SiO2)

Ferruginous Sandstone

Ferruginous Clastic Sedimentary Rock

Granodiorite (containing Biotite and Quartz)

Granodiorite (Plagioclase-rich phaneritic intrusive rock)

Serpentine

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

Rounded pale pebble, likely quartz-rich stone

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

Serpentine-rich rock (possibly lizardite/serpentinite)

Serpentinite, composed chiefly of serpentine-group minerals such as lizardite, antigorite, or chrysotile

Grooved Maun Ball (Maul/Hammerstone-like Concretion)

Calcareous/Ferruginous Concretion in Sandstone Matrix

Quartz-rich pegmatitic rock with possible epidote or chlorite

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

Asphalt (Bituminous Slate/Sandstone)

Asphaltum / Bituminous Rock

Chert (Arrowhead Debitage or Flake)

Microcrystalline silica (SiO2)

Botryoidal prehnite

Prehnite, Ca₂Al(AlSi₃O₁₀)(OH)₂

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

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

Iron-stained Quartz Vein

Silicon Dioxide (SiO2) with Limonite/Hematite inclusions

Quartz-rich breccia or silicified rock

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

Mystic Topaz

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

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

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

Chert (Arrowhead Fragment)

Microcrystalline Quartz (SiO2)

Green Sea Glass

Man-made vitreous material (silica glass)

Chert (often called Flint)

Chert (Microcrystalline Quartz, SiO2)

Basalt

Basalt (Aphanitic Mafic Volcanic Rock)

Chert (Arrowhead/Projectile Point)

Microcrystalline quartz (SiO2)

Unidentified gray metallic object

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

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)

Sandstone (Red/Brown Variety)

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

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