Rock (Likely Sedimentary)

Quartz (likely milky quartz or a stained variety)

Silicon Dioxide (SiO₂)

Petrified Wood

Silicified Wood (primarily Quartz/Chalcedony, SiO2)

Quartzite (River Cobble)

Quartzite (primarily SiO2)

Jasper (specifically Bloodstone or Heliotrope variety)

Silicon Dioxide (SiO2) with iron oxide inclusions

Granite Cobble

Granite (Phaneritic igneous rock composed of Quartz, Feldspar, and Mica)

Granite Pebble

Felsic intrusive igneous rock (consisting primarily of Quartz and Feldspar)

Black Onyx

Chalcedony (SiO2)

Banded Rhyolite (likely Green Jasper/Agate variety)

Silicon Dioxide (SiO2) with mineral inclusions

Painted Rock

Weathered Sedimentary Rock (Painted)

Limestone

Calcareous sedimentary rock (CaCO3)

Sandstone (Quartz-rich)

Arenite (primarily SiO2)

Weathered basalt or other dark volcanic rock

Likely basalt; predominantly plagioclase feldspar and pyroxene, possibly olivine and iron oxides

Quartz-veined Sandstone

Quartzite-veined Arenite / SiO2 and quartz sand

Jasper with Purple Fluorite or Chalcedony

Silicon Dioxide (SiO2) with mineral inclusions

Jasper Pendant

Chalcedony (Quartz) - SiO2

Fossil-bearing ironstone or weathered concretion

Indeterminate; likely ferruginous sandstone/concretion containing a partial fossil impression

Quartz-rich quartzite or silicified stone

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

Tumbled pale quartz/chalcedony fragment

Quartz (SiO₂), possibly microcrystalline chalcedony

Tumbled reddish-brown pebble, likely sandstone or iron-rich quartzite

Probable ferruginous sandstone (quartz-rich; SiO₂ with iron oxides), possibly quartzite

Red Jasper (or Banded Jasper)

Silicon Dioxide (SiO2 with Hematite impurities)

Man-made Ceramic / Clay Figurine

Aluminosilicate Ceramic (Processed Clay)

Sandstone

Arenite (SiO2 composition primarily)

Hag Stone

Perforated sedimentary rock (typically flint, chert, or limestone)

White quartz in dark matrix (likely quartz-bearing breccia or polished composite specimen)

Quartz, SiO₂, in an unidentified dark silicate matrix

Banded agate (likely fire agate or iron-stained chalcedony)

Microcrystalline quartz, SiO₂; chalcedony with iron-oxide inclusions

Sandstone

Arenite (with iron oxide cement)

Weathered quartz-rich sandstone or quartzite

Quartzite (predominantly SiO₂), possibly strongly cemented sandstone

Chert

Silicon Dioxide (SiO2)

Agate Geode

Silicon Dioxide (SiO2)

Sandstone (with Chert/Quartzite nodules)

Clastic sedimentary rock (primarily SiO2)

Worn River Pebble with Fossil Indentation

Sedimentary Rock with Fossil Infill

Sandstone (Quartz Sandstone)

Arenite (primarily SiO2)

Sandstone

Arenite (composed primarily of SiO2)

Quartz Geode

Silicon Dioxide (SiO2)

Weathered fossiliferous limestone

Bioclastic limestone, chiefly calcite (CaCO₃)

Jasper

Silicon dioxide (SiO2)

Coal

Bituminous Coal / Anthracite

Quartz Geode

Crystalline Quartz (SiO2) within a sedimentary/igneous host

Quartz Geode

Silicon Dioxide (SiO2) in a sedimentary or volcanic host

Foliated schist, likely mica schist

Mica schist; chiefly quartz (SiO₂), muscovite/biotite mica, and feldspar

Vuggy Quartz on Matrix

Crystalline Silicon Dioxide (SiO2)

Sandstone (Ferruginous)

Sandstone (primarily SiO2 with iron oxide Fe2O3 staining)