Sedimentary (Anthropogenic)

Weathered banded gneiss

Foliated quartz–feldspar-rich gneiss; exact mineral identification requires closer examination

Iron-rich slate or phyllite

Fine-grained, foliated metamorphic rock, likely iron-oxide-stained slate/phyllite; exact identification requires examination

Fossiliferous limestone

Calcite-rich limestone (primarily CaCO₃), possibly containing fossil fragments

Banded gneiss

Foliated gneiss, likely quartz–feldspar–mica gneiss

Banded gneiss

Quartz–feldspar gneiss, possibly biotite-bearing; exact identification requires testing

Banded gneiss

Gneiss, commonly quartz–feldspar–mica gneiss

Sandstone (Pebble)

Arenite

Brachiopod Fossil

Phylum Brachiopoda

Knightia Fossil in Limestone

Knightia eocaena in micritic limestone

Puddingstone (Gowganda)

Gowganda Formation Conglomerate

Chert (flint), likely a knapped fragment

Microcrystalline quartz (SiO₂), also called cryptocrystalline quartz

Red Jasper

Silicon Dioxide (SiO2) with Hematite impurities

Red Jasper (or Agate/Jasper mixture)

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Chert (Agatized/Chalcedony variety)

Microcrystalline Quartz (SiO2)

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Yellow Jasper

Jasper (Silicon Dioxide, SiO2)

Weathered sandstone block

Quartz-rich sandstone; exact composition cannot be confirmed from the image

Rounded quartz-rich sandstone cobble

Quartz arenite (sandstone), likely iron-stained

Coal

Bituminous Coal / Anthracite

Shale

Shale (fine-grained clastic sedimentary rock)

Sandstone / Weathered Quartzite

Sandstone (Quartz Arenite)

Sandstone

Arenite (Sedimentary rock composed of sand-sized grains, primarily SiO2)

Red Jasper (or Banded Jasper)

Silicon Dioxide (SiO2 with Hematite impurities)

Fossilized gastropod shell

Fossil Gastropoda; shell originally composed chiefly of calcium carbonate (aragonite or calcite)

Sandstone Pebble

Arenite

Sandstone

Arenite

Sidewalk Chalk

Calcium Carbonate (CaCO3) / Gypsum

Tumbled milky quartz

Quartz, SiO₂; trigonal crystal system

Granite with a quartz-rich inclusion

Granite, composed mainly of quartz, feldspar, and mica

Quartz (likely milky or iron-stained quartz)

Quartz, silicon dioxide (SiO₂)

Milky quartz cluster

Quartz (silicon dioxide, SiO₂)

Fossil shark tooth

Fossilized shark tooth; species indeterminate from the image

Tumbled milky quartz

Quartz (silicon dioxide, SiO₂)

Likely banded gneiss

Gneiss (quartz–feldspar–mica-rich rock; exact identification uncertain from the photo)

Milky quartz crystal cluster

Quartz (silicon dioxide, SiO₂)

Banded gneiss

Foliated gneiss, likely quartz–feldspar–mica gneiss

Limonite Geode (Ironstone Concretion)

Limonite [FeO(OH)·nH2O] with possible Quartz or Calcite interior

Galena

Lead Sulfide (PbS)

Jasper

SiO2

Sandstone

Clastic sedimentary rock (quartz arenite)

Red Sandstone

Quartzose Sandstone (Siliciclastic sedimentary rock)

Ironstone concretion

Iron-oxide-cemented sedimentary concretion, commonly hematite/goethite with quartz or clay