Organic Material (Likely A Fruit Or Berry)

Red Jasper

Silicon Dioxide (SiO2) with Hematite impurities

Petrified Wood

Silicified Wood (SiO2 permineralization)

Petrified Wood

Silicified Wood (primarily SiO2)

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood

Silicified Wood (primarily SiO2)

Chert (Chert Nodule)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Cherty Flint/Jasper variety)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Likely weathered basalt or dark volcanic rock

Basalt; primarily plagioclase feldspar and pyroxene, with possible olivine and iron oxides

Likely weathered fossil bone fragment

Indeterminate fossilized bone; taxonomic identification requires microscopy and locality data

Green beryl (likely aquamarine-grade beryl)

Beryl, Be₃Al₂Si₆O₁₈; blue-green color is caused mainly by iron

Tumbled milky quartz (likely chalcedony or quartzite)

Quartz/chalcedony, silicon dioxide (SiO₂)

Dark igneous rock, likely basalt

Basalt; chiefly plagioclase feldspar, pyroxene, and possibly olivine

Dark rounded pebble, likely basalt

Basalt (fine-grained mafic volcanic rock; commonly plagioclase, pyroxene, and olivine)

Polished dark stone, likely basalt

Basalt, a fine-grained mafic volcanic rock composed mainly of plagioclase feldspar and pyroxene, with possible olivine and magnetite

Banded Chert or Agate

Silicon Dioxide (SiO2)

Unakite-like granite with a white feldspar inclusion

Granite, chiefly quartz–feldspar–biotite; pale inclusion likely albite/orthoclase feldspar

Sandstone (likely Arkosic or Quartzose)

Arenite (SiO2 based with mineral inclusions)

River Pebble (Gravel)

Clastic sedimentary rock (likely Siltstone or Mudstone pebble; SiO2 with various impurities)

Likely weathered sandstone or quartzite

Quartz-rich sandstone; possibly metamorphosed to quartzite (SiO₂-dominant)

Blue-green tourmaline (likely indicolite)

Elbaite tourmaline, Na(Li1.5Al1.5)Al6(BO3)3Si6O18(OH)4

Chert (Jasper)

Silicon Dioxide (SiO2)

White quartz-rich pebble

Likely quartzite or milky-quartz pebble (SiO₂)

Quartz (likely)

Quartz (SiO2 - Silicon Dioxide)

Rounded quartz-rich pebble

Likely milky quartz (SiO₂), possibly quartzite or a quartz-rich river pebble

Tumbled orange chalcedony or jasper

Microcrystalline quartz (SiO₂), likely iron-stained chalcedony/jasper

Tumbled green aventurine (likely)

Quartz (SiO₂) with fuchsite or other green mica inclusions

Limestone

Calcium Carbonate (CaCO3)

Tumbled carnelian/chalcedony

Microcrystalline quartz (SiO₂), likely iron-stained chalcedony

Rounded gray-brown cobble, likely weathered sandstone or quartzite

Tentatively quartz-rich sandstone (SiO₂-dominated); exact identification requires hardness and acid tests

Weathered iron-rich sandstone or lateritic rock

Quartz-rich sandstone with iron-oxide/hydroxide cement; possible goethite-bearing laterite

Weathered porphyritic pebble

Likely porphyritic volcanic rock, possibly andesite or rhyolite

Unakite (likely epidote–feldspar rock)

Epidote–K-feldspar–quartz aggregate; commonly approximated as pink orthoclase/microcline + green epidote + quartz

Chert / Jasper

Cryptocrystalline Silica (SiO2)

Fossilized tooth, likely mammalian molar

Indeterminate Mammalia; mineralized dentine and enamel

Quartz-rich quartzite or silicified stone

Quartzite; predominantly microcrystalline quartz (SiO₂), with minor iron-oxide staining and possible feldspar/clay impurities

Chert (Flint)

Microcrystalline Quartz (SiO2)

Flint

Chert (Cryptocrystalline Quartz, SiO2)

Porous quartz-rich rock, likely weathered rhyolite or silicified volcanic breccia

Rhyolite or volcanic breccia; predominantly microcrystalline quartz (SiO₂) with altered feldspar and iron oxides

Quartz-rich pegmatite or quartz vein rock

Mostly quartz (SiO₂), with probable feldspar and iron-oxide staining

Likely polished dark stone or glassy mineral bead

Indeterminate; possibly obsidian, hematite, or a dark agate

Flint or chert fragment

Microcrystalline quartz (SiO₂), likely flint/chert

Polished limestone or marble slab

Calcite-rich carbonate rock; likely marble (CaCO₃)