Mineral (Sedimentary Context)

Jasper with Iron Staining

Silicon Dioxide (SiO2) with impurities

Chert (Nodule)

Silicon Dioxide (SiO2)

Mixed rock specimens; likely pink feldspar/quartz and a dark, mica-bearing rock

Tentative visual identification: pink K-feldspar–quartz-rich granite/pegmatite fragments and a dark amphibole- or biotite-rich metamorphic rock; exact identification is uncertain from the image

Likely brown chert (flint)

Microcrystalline quartz (SiO₂), variety chert/flint

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

Limestone

Calcium Carbonate (CaCO3)

Weathered quartz-rich rock, likely sandstone or quartzite

Quartz (SiO₂)-rich sandstone; possibly partially metamorphosed quartzite

Chert (Nodule)

Silicon Dioxide (SiO2)

Flint or chert flake/tool

Microcrystalline quartz (chalcedony), SiO₂

Weathered orange-brown stone, possibly iron-stained sandstone

Unconfirmed; likely quartz-rich sandstone with iron-oxide staining

Cobaltian Calcite (Cobaltoan Calcite)

Cobalt-bearing Calcite (Ca,Co)CO3

Jasper (Red Jasper)

Silicon Dioxide (SiO₂)

Kidney Stone (Medical Specimen)

Calcium oxalate monohydrate (Whewellite) / CaC2O4·H2O

Asphalt (Bituminous Pavement Bit)

Bitumen-bound aggregate (Petrochemical-bound composite)

Banded chert or agate

Microcrystalline quartz (chalcedony), SiO₂

Worked flint/chert artifact

Microcrystalline quartz (chalcedony), SiO₂; likely a knapped flint or chert flake/core fragment

Flint/chert projectile point

Microcrystalline quartz (SiO₂), archaeologically worked into a bifacial point

Bronze or iron-age decorated pottery sherd

Archaeological ceramic fragment; likely fired clay with impressed or molded decoration, not a natural rock

Ferruginous Sandstone (Ironstone Conglomerate fragments)

Ferruginous clastic sedimentary rock (SiO2 cemented by Fe2O3)

Vesicular Basalt

Aphanitic Mafic Volcanic Rock

Weathered conglomeratic sandstone

Polymictic conglomerate or pebbly sandstone, likely iron-stained

Likely garnet-bearing metamorphic fragment

Uncertain; possibly almandine garnet in mica schist or amphibolite

Quartz crystal (likely milky or clear quartz)

Quartz, silicon dioxide (SiO₂)

Chert (Nodule)

Cryptocrystalline Silica (SiO2)

Chert Nodule

Microcrystalline Silica (SiO2)

Gneiss (specifically a water-worn pebble)

Gneiss

Black Tourmaline (Schorl)

Schorl (Complex sodium iron aluminum borosilicate)

Magnetite

Magnetite (Fe3O4)

Rounded sandstone pebble

Clastic sandstone, chiefly quartz and feldspar grains cemented by iron oxides and silica

Chert (Flint Nodules)

Silicon Dioxide (SiO2)

Chert (with nodule)

Microcrystalline Quartz (SiO2)

Weathered sandstone or iron-rich sedimentary fragment

Quartz-rich sandstone, possibly ferruginous sandstone (SiO₂-dominant)

Chert (varietal Chalcedony or Flint)

Silicon dioxide (SiO2) - Microcrystalline Quartz

River Cobble (Conglomerate context)

Unconsolidated Fluvial Alluvium (comprised of various lithologies like Quartzite, Granite, or Basalt)

Limestone

Calcium Carbonate (CaCO3)

Graywacke

Graywacke

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Fossilized cylindrical shell or bone fragment

Indeterminate biogenic carbonate or phosphatic fossil; possible fragment of a tubular shell (e.g., scaphopod) or hollow bone

Sodalite

Sodalite (Na8(Al6Si6O24)Cl2)

Fluorite

Fluorite (Calcium Fluoride - CaF2)

Chert or flint flake

Cryptocrystalline microcrystalline quartz (SiO₂), likely chert/flint

Banded iron formation fragment

Banded iron formation (BIF), composed mainly of hematite/magnetite and chert (SiO₂)