Anthropogenic Material

Flint (chert), likely chalcedony-rich variety

Microcrystalline quartz, SiO₂; flint is a dense cryptocrystalline form of chert

Micaceous schist (likely quartz–mica schist)

Quartz–mica schist; chiefly quartz (SiO₂), muscovite/biotite micas, with possible feldspar and accessory iron oxides

Unidentified gray stone/concrete-like fragment

Indeterminate; likely a fine-grained carbonate or cementitious geological fragment

Small weathered stone, possibly quartz-rich sandstone

Indeterminate siliciclastic rock; likely quartz-bearing sandstone or chert fragment

Small rounded pebble, likely weathered sandstone or iron-rich rock

Indeterminate; possibly quartz-rich sandstone (SiO₂) with iron-oxide staining

Iron-rich chert or jasper fragment

Microcrystalline quartz (SiO₂), colored by iron oxides/hydroxides

Tumbled chert or chalcedony pebble

Microcrystalline quartz (SiO₂), likely chert/chalcedony

Siltstone

Siltstone (composed of clastic quartz and feldspar grains)

Quartz Pebble

Silicon Dioxide (SiO2)

Botryoidal chalcedony (likely agate/jasper matrix)

Microcrystalline quartz, SiO₂; commonly containing iron-oxide impurities

Tumbled blue stone, likely blue aventurine or dyed quartz

Quartz (SiO₂), possibly with fuchsite inclusions; exact identification requires testing

Rounded iron-stained quartzite or sandstone pebble

Quartzite, predominantly SiO₂, with iron-oxide staining

Weathered iron-rich rock, likely laterite or ironstone

Ferruginous laterite/ironstone, composed mainly of goethite (FeO(OH)), hematite (Fe₂O₃), and clay minerals

Siltstone

Siltstone (composed of microscopic quartz and clay minerals)

Sandstone (likely Quartzose Sandstone pebble)

Arenite (primarily SiO2)

Quartzite pebble

Quartzite (SiO2)

Quartzite

Quartzite (composed primarily of SiO2)

Bull Quartz (White Quartz)

Silicon Dioxide (SiO2)

Red jasper in a gray host rock (likely jasperized volcanic rock)

Microcrystalline quartz (SiO₂), iron-oxide–colored jasper, in a fine-grained volcanic or sedimentary matrix

Petrified Wood

Silicified wood (primarily Silicon Dioxide, SiO2)

Chert / Flint

Microcrystalline quartz (SiO2)

Chert (Flint)

Microcrystalline quartz (SiO2)

Chert (Flint)

Microcrystalline Quartz (SiO2)

Greenish quartz-bearing rock, possibly serpentine or aventurine

Tentatively quartz (SiO₂) with green inclusions; exact identification requires testing

Polished brecciated jasper (likely Picasso jasper)

Brecciated microcrystalline quartz/chalcedony; mainly SiO₂ with iron- and manganese-rich matrix

Likely weathered iron-rich quartz or chert

Microcrystalline quartz (SiO₂), possibly limonite/goethite stained

Polished dragon blood jasper

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

Likely calcite-rich limestone

Calcite (CaCO₃), probably micritic or fossiliferous limestone

Petrified Wood / Fossilized Wood

Silicified Wood (Silicon Dioxide - SiO2)

Likely quartz-rich river pebble

Milky quartz or quartz-bearing granitic/gneissic fragment (SiO₂-dominant)

Jasper (likely red/brown jasper)

Microcrystalline quartz/chalcedony, SiO₂, colored mainly by iron oxides

Likely tumbled jasper or iron-stained quartzite

Microcrystalline quartz (SiO₂), possibly quartzite with iron-oxide inclusions

Brick fragment (Man-made material)

N/A (Fired clay)

Serpentinite (likely)

Serpentinite, dominated by serpentine-group minerals (antigorite, lizardite, chrysotile), commonly with magnetite and relic olivine/pyroxene

Dyed tumbled quartz (likely quartzite or quartz crystal)

Quartz, silicon dioxide (SiO₂)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Blue-green botryoidal mineral specimen, likely chrysocolla or chrysocolla-bearing quartz

Chrysocolla (hydrated copper phyllosilicate; variable composition, commonly approximated as (Cu,Al)₂H₂Si₂O₅(OH)₄·nH₂O)

Blue-green copper mineral-bearing rock, likely chrysocolla with malachite

Chrysocolla (hydrated copper aluminosilicate, approximately (Cu,Al)₂H₂Si₂O₅(OH)₄·nH₂O) with malachite (Cu₂CO₃(OH)₂), possibly in altered host rock

Crushed Granite / Landscaping Gravel

Granitoid

Diamond

Carbon (C)

Meteorite

Chondrite / Iron-Nickel Meteorite

Diamond

Carbon (C)