Mineral, Sediment

Tumbled jasper

Microcrystalline quartz (SiO₂), commonly iron-rich jasper

Tumbled orange jasper or iron-rich chert

Microcrystalline quartz (SiO₂), colored by iron oxides

Tumbled quartz pebble

Quartz (silicon dioxide, SiO₂)

Tumbled jasper or chert

Microcrystalline quartz (SiO₂), possibly iron-bearing jasper

Tumbled jasper (likely brecciated or orbicular jasper)

Microcrystalline quartz (SiO₂), with iron-oxide inclusions

Likely tumbled jasper or iron-rich chert

Microcrystalline quartz (SiO₂), potentially hematite/goethite-bearing

Amber (Rough)

Amber (Fossilized Tree Resin, succinite)

Amber

Amber (Amorphous Organic Hydrocarbon)

Petrified Wood

Silicified Wood (SiO2)

Banded chert pebble

Microcrystalline quartz (SiO₂), likely ferruginous or jaspery chert

Petrified Wood

Fossilized wood, permineralized wood (typically composed of SiO2)

Petrified Wood

Silicified wood (primarily Silicon Dioxide, SiO2)

Polished fossil ammonite

Ammonite cephalopod fossil, likely an ammonite mold/cast in calcite or aragonite-derived mineralization

Likely ironstone or weathered chert with an iron-oxide spot

Silicified sedimentary rock, possibly ferruginous chert (microcrystalline SiO₂ with Fe oxides)

Fossiliferous limestone with colonial coral

Calcite (CaCO₃) limestone containing fossil tabulate or rugose coral colonies

Painted River Pebble (likely Basalt or Greywacke)

Aphanitic Lithic Clast with Anthropogenic Pigment coating

Weathered basalt pebble with a vesicle

Basalt (fine-grained mafic volcanic rock; commonly plagioclase, clinopyroxene, and Fe-Mg oxides)

Rhodonite

(Mn,Fe,Mg,Ca)SiO3

Weathered fossil shell fragment

Likely molluscan shell, composed mainly of calcium carbonate (aragonite or calcite); exact taxon is indeterminate from the image

Shale or Mudstone

Argillaceous sedimentary rock

Gravel and Pavement Aggregates

Unconsolidated rock fragments / detrital sediments

Polished brecciated jasper

Microcrystalline quartz (SiO₂), likely iron-oxide-rich jasper

Petrified Wood

Silicified wood (Quartz / Chalcedony replacement)

Possible fossil tooth or bone fragment

Indeterminate fossilized vertebrate material; species cannot be identified reliably from this image

Fossil Shark Tooth

Selachii fossil

Schist

Mica schist, typically muscovite–biotite quartz schist

Fossil Coral in Limestone

Scleractinia (Anthomastodon or similar) in Sedimentary Calcarenite

Fossilized Echinoid

Echinoidea (likely of the order Echinoidea)

Fossil Shell

Phylum Mollusca (Gastropod fossil)

Blue kyanite

Kyanite (Al₂SiO₅)

Pyrite

Iron Sulfide (FeS2)

Iron-stained quartz (likely quartzite or quartz vein fragment)

Quartz, SiO₂, with iron-oxide staining; host rock appearance suggests quartzite or a quartz vein

Hematite-rich ironstone concretion

Hematite (Fe₂O₃), likely mixed with goethite/limonite and silica

Polished/tumbled jasper, likely brecciated jasper

Jasper: microcrystalline quartz (SiO₂), with iron-oxide and other mineral impurities

Fossilized shell fragment

Indeterminate fossil mollusk; likely a silicified or mineral-replaced bivalve/gastropod fragment

Brown chert or jasper pebble

Microcrystalline quartz (SiO₂), likely iron-oxide-bearing chert/jasper

Amber

Succinite (organic fossilized resin)

Jasper (Iron Oxide Rich)

Silicon Dioxide (SiO2) with Fe2O3 (Hematite/Goethite) inclusions

Generic Pebble / Small Rock Fragment

Lithic fragment / Weathered rock particle

Iron-rich concretion or weathered ironstone

Limonite/goethite-rich ironstone; commonly hydrated iron oxides such as FeO(OH)·nH₂O

Fossil Shark Tooth

Chondrichthyes (Class)

Weathered basalt or andesite cobble

Fine-grained mafic to intermediate volcanic rock; commonly plagioclase ± pyroxene, amphibole, and iron oxides