Industrial Byproduct (Anthropogenic Rock Like Material)

Diamond (or Cubic Zirconia)

Carbon (C) or Zirconium Dioxide (ZrO2)

Likely weathered fossil bone fragment

Indeterminate fossilized bone; taxonomic identification requires microscopy and locality data

Fossilized oyster or bivalve shell

Fossil Gryphaeidae or Ostreoidea; calcitic shell, CaCO₃

Bauxite

Bauxite (Al(OH)3, AlO(OH))

Schist (Greenschist / Mica Schist)

Metamorphic rock rich in platy minerals (e.g., Chlorite/Mica schist)

Possible basaltic volcanic rock or iron-rich meteorite

Likely basalt (plagioclase–pyroxene rock); meteorite status cannot be confirmed visually

Likely iron meteorite (stony-iron or weathered iron-rich meteorite)

Provisional identification: meteoritic Fe–Ni alloy, mainly kamacite/taenite; exact classification requires chemical and petrographic testing

Red Sandstone

Arenite (primarily Quartz with Hematite cement)

Puddingstone / orbicular jasper-like rock

Likely orbicular rhyolite or altered volcanic breccia, composed mainly of quartz, feldspar, and iron-bearing alteration minerals

Polished brecciated jasper

Microcrystalline quartz (SiO₂), commonly colored by iron oxides

Sandstone

Arenite (SiO2 based with quartz grains)

Titanium Aura Quartz (Bismuth-coated Druzy)

Silicon Dioxide (SiO2) with Titanium/Metal vapor coating

Smooth gray pebbles

Unidentified rounded rock fragments; composition cannot be determined from the image

Weathered gray rock, likely basalt or andesite

Fine-grained mafic to intermediate volcanic rock; likely basalt (plagioclase ± pyroxene, possibly altered)

Weathered vuggy quartz-rich rock (probable silicified limestone or quartz breccia)

Microcrystalline quartz (SiO₂) with calcite (CaCO₃), iron oxides, and minor clay minerals

Green glassy slag (often sold as “sea glass” or “green obsidian”)

Industrial vitreous slag; primarily amorphous silicate glass, composition variable

Sea Glass

Man-made silicate glass

Basalt

Basalt (Ma-Fe Silicate)

Diamond (or diamond simulant)

C

Blue glass-like tumbled specimen

Most likely cobalt-blue slag glass or manufactured glass; not confidently identifiable as a natural mineral from the image

Shale or Siltstone

Sedimentary Clastic Rock (Variable mineral composition including quartz and clay minerals)

Graphite-veined Quartzite

Meta-sedimentary Quartzite with Carbonaceous/Graphitic Inclusions (SiO2 + C)

Vesicular Basalt (Lava Rock)

Basalt

Prasiolite (Green Quartz) / Sea Glass Amalgam

SiO2 (Silicon Dioxide)

Polished ocean jasper

Orbicular jasper (microcrystalline quartz, SiO₂)

Quartz pebble

Silicon dioxide (SiO2)

Tumbled tree agate (dendritic agate)

Cryptocrystalline quartz, SiO₂, with manganese/iron-oxide dendrites

Red Sandstone

Clastic Sandstone (typically Quartz-rich with Iron Oxide)

Coal

Combustible sedimentary rock

Likely garnet-bearing schist or weathered garnet amphibolite

Garnet (almandine, Fe₃Al₂Si₃O₁₂) in a mica-rich metamorphic matrix

Iron-stained quartz-rich breccia

Silicified, limonite/goethite-stained breccia; chiefly SiO₂ (quartz) with FeO(OH)·nH₂O iron oxides

Iron-rich meteorite candidate

Provisional: stony-iron or iron meteorite; exact classification requires testing

Diamond (or Diamond Simulant)

Carbon (C)

Banded chert or silicified limestone nodule

Microcrystalline quartz (SiO₂), possibly replacing carbonate fossils

Possible iron-rich basalt or slag-like volcanic rock

Basalt, tentatively; mineral composition likely plagioclase, pyroxene, and iron oxides

Bauxite

Bauxite (Al2O3·2H2O)

Amethyst-bearing quartz cluster

Quartz, SiO₂; purple coloration commonly from iron-related defects and irradiation

Serpentine

Hydrous magnesium iron silicate, (Mg,Fe)3Si2O5(OH)4

Polymict breccia

Lithic breccia; clast-rich, iron-stained breccia

Rounded gray-brown pebble

Indeterminate; likely weathered quartz-rich sandstone or fine-grained volcanic rock

Unakite-like jasper / epidote–feldspar rock

Epidote–feldspar–quartz aggregate; commonly marketed as unakite or brecciated jasper

Chert (specifically Flint or Dark Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)