Not A Geological Specimen

Conglomeratic concrete or asphalt aggregate surface with dark bituminous chunks

Polymictic gravel aggregate; dark pieces likely bitumen/asphalt, not a natural rock

Titanium-coated Metal Cube (Man-made Fidget Toy)

Titanium-anodized or electroplated alloy (e.g., Ti-coated Zinc or Aluminum)

Note regarding baguette production (not a rock)

Digital text image - Somali language

Banded agate bangle

Agate (microcrystalline quartz, SiO₂), likely gray-blue chalcedony with parallel banding

Banded agate tower (likely onyx/chalcedony)

Microcrystalline quartz, SiO₂; commonly called banded agate or black-and-white onyx

Sandstone

Arenite (principally SiO2)

Porphyry

Porphyritic igneous rock

Granite

Intrusive Igneous Rock

Shale (with Iron Staining)

Argillaceous mudstone / Shale

Argillite

Argillite (compact, clay-rich sedimentary rock)

Chert / Flint

Microcrystalline quartz (SiO2)

Quartzite Pebble

Quartzite (SiO2)

Polished amber-like agate or jasper carving

Likely chalcedony (microcrystalline SiO₂), possibly iron-stained carnelian/jasper; exact identification requires testing

Polished orbicular granite

Orbicular granite, commonly quartz–feldspar–biotite granite with orbicules

Man-made Ceramic / Clay Figurine

Aluminosilicate Ceramic (Processed Clay)

Engraved polished dark stone (likely slate or basalt)

Probable fine-grained slate (microcrystalline phyllosilicates), possibly basalt; exact identification requires testing

Colorless faceted gemstone (most likely synthetic cubic zirconia)

Cubic zirconia, ZrO₂ (likely synthetic); natural alternatives include quartz or diamond

Mixed tumbled stone collection

Assorted minerals, likely including quartz, jasper, agate, and possibly obsidian or hematite

Unknown Organic Object (likely a berry or fruit)

Not applicable; this is not a geological specimen. If it were a cranberry, its scientific name would be Vaccinium macrocarpon; if a cherry, it would be Prunus avium or Prunus cerasus.

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

Anthracite

Anthracite Coal

Mixed collection of tumbled minerals and rough specimens

Multiple species visible; likely fluorite, quartz/chalcedony, pyrite, tiger’s eye, rose quartz, and possibly labradorite or agate

Man-made earbud charging case (Not a rock or mineral)

Acrylonitrile Butadiene Styrene (ABS) Plastic with electronic components

Vein Quartz in Basalt or Mafic Rock

Silicon Dioxide (Quartz veins in volcanic host rock)

Polished septarian nodule

Septarian concretion; calcite/aragonite and barite-filled fractures in a carbonate-rich mudstone, commonly with pyrite

Pearl

Pearl; primarily aragonite (CaCO₃) with conchiolin

Glass / Silicon Dioxide (Man-made)

SiO2 (Amorphous Silicon Dioxide)

Quartz in Greenstone

Metamorphic rock with quartz vein (SiO2 / mixed silicates)

Possible basalt or iron-rich slag-like geological specimen

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

Flint

SiO2 (Microcrystalline quartz / Chert)

Basalt

Mafic extrusive igneous rock

Quartzite Pebble

Metamorphic Quartzite (predominantly SiO2)

Chert (Flint)

Microcrystalline quartz (SiO2)

Tumbled translucent quartz or chalcedony fragment

Silicon dioxide, SiO₂; likely quartz/chalcedony

Lapidary Wax (imitation/wax model)

Hydrocarbon wax blend with colorant (imitating Lapis Lazuli/Emerald)

Blue Slag Glass

Amorphous Silica (Industrial byproduct)

Green cabochon gemstone pendant, likely turquoise or dyed green turquoise

Probably turquoise, CuAl₆(PO₄)₄(OH)₈·4H₂O; exact identification requires testing

N/A - Man-made object (Jewelry Chain)

Antiqued or Oxidized Metal Chain (often Steel or Brass)

Polished orbicular/porphyritic granite or breccia

Likely potassium-feldspar–quartz granite with amphibole/biotite and epidote; exact variety uncertain from the image

Pearl

Biogenic calcium carbonate; mainly aragonite (CaCO₃), sometimes calcite, in nacre

River Cobble (Quartzite / Granitic Gneiss)

Metamorphic Quartzite / Granitic Gneiss

Exposed Aggregate Concrete (Pea Gravel)

Concrete with Siliceous Alluvial Gravels