Industrial Byproduct (Anthropogenic Rock)

Note: Item is not a geological specimen

Homo sapiens (Dermal Appendage: Pilus)

Quartz Geode (with possible Manganese or Goethite coating)

Silicon Dioxide (SiO2)

Basalt with Quartz/Calcite Veins

Aphanitic Mafic Igneous Rock (Hydrothermal Veined)

Quartzite

Quartzite (SiO2)

Greywacke (Sandstone)

Lithic wacke

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

Weathered quartz-bearing rock fragment

Indeterminate; likely quartz-rich granite or silicified host rock with iron-oxide staining

Crushed Stone (Gravel/Aggregates)

Crushed rock aggregate (varied composition including Granite, Limestone, and Quartz)

Polished picture jasper (likely)

Silica-rich microcrystalline quartz, SiO₂, with iron-oxide and other mineral inclusions

Blue Calcite Sphere

Calcium Carbonate (CaCO3)

Weathered pebble, possibly limestone

Unidentified carbonate or silicate rock; the image is insufficient for a definitive identification

Milky quartz

Quartz (silicon dioxide, SiO₂)

Small dark metallic-looking rock fragment

Undetermined; possibly iron oxide-rich material or a metallic mineral

Basalt

Mafic Igneous Rock

Basalt

Mafic Igneous Rock

Basalt

Mafic Igneous Rock

Pumice

Pumice (felsic volcanic rock)

Pumice

Pumice (volcanic glass)

Bauxite

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

Agate

Silicon Dioxide (Chalcedony), SiO2

Uncertain dark-and-white rock fragment

Likely a mixed lithic specimen, possibly quartz-bearing granite or ore; exact identification is not possible from the photograph

Milky quartz vein material

Quartz, silicon dioxide (SiO₂), likely massive vein quartz

Quartz-rich pegmatite (likely feldspar and quartz)

Granitic pegmatite composed mainly of quartz (SiO₂) and feldspars

Serpentine

Serpentine group ((Mg,Fe,Ni,Al,Zn,Mn)3(Si,Fe)2O5(OH)4)

Note: Item is not a geological specimen

Guitar Components (Steel, Nickel, Plastic, Wood)

Limestone

Calcium Carbonate (CaCO3)

Dark basaltic rock, possibly vesicular basalt

Basalt; chiefly plagioclase feldspar, clinopyroxene, and commonly olivine or iron-titanium oxides

Bicolor Quartz (Milk Quartz with Slag or Dark Inclusions)

Silicon Dioxide (SiO2) with impurities

Mixed collection of rocks and minerals

Assorted specimens; visible pieces may include quartz, feldspar, jasper, and other common minerals, but individual identification is uncertain from the image

Moss-covered Rock Fragment

Weathered Rock Fragment with Epilithic Growth

Likely mica schist

Mica-rich schist, likely quartz–muscovite/biotite schist

Granite Pegmatite

Coarse-grained Granite (SiO2 - Aluminum and Alkalies)

Rounded weathered stone (likely river cobble)

Undetermined; possibly fine-grained volcanic rock such as andesite

Quartzite Pebble

Quartzite (SiO2)

Quartz with Iron Staining

Silicon Dioxide (SiO2) with Ferruginous Oxides

Limestone

Calcium Carbonate (CaCO3)

Weathered rock fragment

Unidentified, likely fine-grained mafic volcanic rock

Unidentified Rock Fragment

Unknown

Quartz Geode Fragment

Silicon Dioxide (SiO2)

Mica Schist

Mica Schist (primarily Muscovite or Biotite sheet silicates)

Pink Granite

Phaneritic Felsic Igneous Rock (Granite)

Bauxite

AlOx(OH)3-2x (mixture of Gibbsite, Boehmite, and Diaspore)