Organic Material (Likely A Fruit Or Berry)

Chert (variations include Flint/Jasper)

Chert (SiO2)

Shale

Clastic sedimentary rock (primarily clay and silt minerals)

Brecciated quartz-rich rock, possibly silicified breccia

Silica-rich breccia; chiefly microcrystalline quartz (SiO₂), with possible calcite and iron-oxide staining

Iron-stained limestone or coral fragment

Calcite-rich carbonate rock; chiefly CaCO₃ (exact identification is uncertain from the image)

Weathered blue-gray calcite/aragonite fragment

Calcium carbonate (CaCO₃), probably calcite; possibly shell-derived aragonite

Tektite (Indochinite)

Tektite (High-silica natural glass)

Limestone with Calcite Crust

Sedimentary Calcium Carbonate (CaCO3)

Weathered sandstone or tuff fragment

Likely quartz-rich sandstone (SiO₂) or porous volcanic tuff; exact identification requires testing

Brown Chert

Microcrystalline Quartz (SiO2)

Chert (Flint)

Microcrystalline Quartz (SiO2)

Pink/red faceted gemstone, likely synthetic ruby or pink sapphire

Corundum, aluminum oxide (Al₂O₃); likely lab-grown or treated material

Tumbled dark green stone, likely serpentine or greenstone

Serpentinite (hydrated magnesium silicate minerals, chiefly antigorite/lizardite); possible chlorite-rich greenstone

Tumbled yellow calcite

Calcite (calcium carbonate, CaCO₃)

Travertine (Tufa)

Travertine (Aragonite/Calcite form of Calcium Carbonate, CaCO3)

Iron-rich weathered stone, possibly hematite-rich ironstone

Hematite/goethite-bearing ironstone; predominantly Fe₂O₃ and FeO(OH)

Limonite (Ironstone)

Limonite (mixture of hydrated iron(III) oxide-hydroxides)

Chert

Cryptocrystalline Quartz (SiO2)

Chert (and Flint)

Silicon Dioxide (SiO2)

Chert (Flint)

Silicon Dioxide (SiO2)

Tumbled blue-green stone, likely aquamarine-bearing pegmatite or blue apatite

Probable fluorapatite, Ca5(PO4)3(F,Cl,OH), though visual identification is uncertain

Tumbled dark blue-green stone, likely labradorite or indigo gabbro

Indeterminate; possible feldspar-rich labradorite (plagioclase, NaAlSi₃O₈–CaAl₂Si₂O₈)

Feldspar-rich igneous rock, likely granite or gneiss fragment

Granite-like quartz–feldspar rock; exact identification is uncertain from the blurred image

Blue Sphalerite (likely dyed or treated Druzy Quartz/Agate)

Zinc Sulfide (ZnS) or Silicon Dioxide (SiO2) with trade-name enhancement

Pearl (likely Freshwater or Akoya Cultured)

Aragonite / Conchiolin composite (CaCO3)

Fossil shell fragment, likely brachiopod or bivalve

Indeterminate fossilized carbonate shell; possibly Spiriferida (brachiopod)

Chert (variant Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Weathered sandstone fragment

Sandstone, primarily quartz (SiO₂) with feldspar and iron-oxide cement

Chert (specifically Flint or Dark Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Fossiliferous Limestone

Bioclastic Limestone (CaCO3)

Amber

Succinite (C10H16O)

Porphyritic granite (likely weathered granitic rock)

Granite; chiefly quartz, alkali feldspar, plagioclase, and biotite/hornblende

Probable weathered granite or granitic gneiss

Granite/granitic gneiss; mainly quartz, feldspar, and mica

Quartzite (River Cobble)

Metamorphic Quartz-rich Rock

Quartz (worked as a tool or artifact)

Silicon Dioxide (SiO2)

Likely basalt with a pale mineral-filled vesicle

Vesicular basalt, probably containing calcite or zeolite (uncertain from image)

Chert (Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Amber

Succinite (organic gemstone, approx. C10H16O)

Limestone

Sedimentary rock composed mainly of calcium carbonate (CaCO3)

Milky quartz with dark host-rock inclusions

Quartz (SiO₂), likely in a granitic or metamorphic matrix

Chert (River Pebble)

Microcrystalline silica (SiO2)

Chert

Chert (SiO2)

Iron-rich chert or jasper pebble

Microcrystalline quartz (SiO₂), colored by iron oxides