Organic Material (Likely A Fruit Or Berry)

Yellow Jasper (Iron-stained Chert)

Silicon Dioxide (SiO2) with iron oxide (Limonite/Goethite) inclusions

Small quartz-rich pebble

Quartz (SiO₂), possibly quartzite or weathered granite fragment

Precious Opal

Hydrated Silica (SiO2·nH2O)

Travertine

Calcareous Tufa (CaCO3)

Likely dark rounded pebbles

Indeterminate; possibly basalt or a dark mafic mineral such as hornblende/biotite

Milky Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Chert (varieties include Flint and Jasper)

Silicon Dioxide (SiO2)

Sandstone (Ferruginous)

Arenite (primarily SiO2 with Fe2O3 cement)

Likely vesicular basalt (scoria)

Basaltic volcanic rock, chiefly plagioclase, pyroxene, and possibly olivine

Serpentinite (likely polished/tumbled)

Serpentinite; chiefly serpentine-group minerals, commonly antigorite, lizardite, and chrysotile, with magnetite and accessory carbonates

Tumbled nephrite jade (likely)

Nephrite jade; fibrous amphibole aggregate, chiefly actinolite–tremolite, Ca₂(Mg,Fe)₅Si₈O₂₂(OH)₂

Tumbled yellow chalcedony (likely citrine or yellow quartz)

Quartz, SiO₂; potentially microcrystalline chalcedony

Granite

Phaneritic intrusive igneous rock (consisting mainly of Quartz, Alkali Feldspar, and Plagioclase)

Septarian Nodule

Septarian Concretion (Calcite, Aragonite, and Limestone)

Milky Quartz with Iron Staining

Quartz (Silicon Dioxide, SiO2)

Tumbled jasper, likely red/brown jasper

Microcrystalline quartz (chalcedony), SiO₂, colored by iron oxides

Weathered, iron-stained quartz-rich pebble (uncertain identification)

Microcrystalline quartz, SiO₂, with iron-oxide/hydroxide staining and dark matrix inclusions

Rounded quartz-rich pebble

Chert or quartzite pebble (tentative; mostly microcrystalline quartz, SiO₂)

Tumbled jasper or chalcedony pebble

Microcrystalline quartz (SiO₂), likely jasper/chalcedony with iron-oxide staining

Chert (Cherty Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Flint variety)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (specifically Flint or Jasper variant)

Microcrystalline quartz (SiO2)

Greenstone (likely serpentinite)

Serpentinite; mainly serpentine-group minerals, Mg₃Si₂O₅(OH)₄, with possible magnetite, chlorite, or other altered minerals

Likely basalt fragment

Basalt; fine-grained mafic volcanic rock, chiefly plagioclase and pyroxene with possible olivine

Banded Chert (River Siltstone)

Microcrystalline Quartz (SiO2)

Chert Pebble with Quartz Veins

Microcrystalline Quartz (SiO2)

Chert (Field Flint)

Microcrystalline Quartz (SiO2)

Weathered iron-rich concretion or laterite fragment

Ferruginous concretion, likely goethite/limonite (hydrated iron oxides) in a clay-rich matrix

Petrified Wood

Silicified Wood (SiO2 - Silicon Dioxide)

Polished orbicular jasper (likely ocean jasper)

Jasper, microcrystalline quartz (SiO₂), colored by iron oxides and other inclusions

Tumbled pink chalcedony (likely pink agate/jasper)

Microcrystalline quartz, SiO₂, with iron-oxide coloring

Green cabochon gemstone, likely aventurine or dyed chalcedony

Indeterminate from image; possible quartz variety (SiO₂), including aventurine quartz or chalcedony

Conglomerate

Clast-supported polymict conglomerate

Chert (Yellow Jasper)

Microcrystalline Quartz (SiO2)

Quartz-rich breccia or altered granite fragment

Polymineralic quartz–feldspar rock, likely hydrothermally altered granite/pegmatite

Pink-and-gray quartz-rich pegmatite, possibly rose quartz with feldspar

Quartz (SiO₂) with K-feldspar/plagioclase; likely pegmatitic granite

Gray chalcedony (microcrystalline quartz)

Chalcedony, SiO₂; likely common gray/blue-gray variety

Purple fluorite (likely cubic crystal aggregate)

Fluorite, calcium fluoride (CaF₂)

Chert (Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Fossilized Shark Tooth (Fragment)

Elasmobranchii gen. indet.

Travertine (Tufa)

Calcium Carbonate (CaCO3)

Polished ammonite fossil

Ammonoidea (likely a Jurassic or Cretaceous ammonite), preserved in limestone/mudstone