Not A Rock Or Mineral

Vesicular Basalt / Scoria pebble

Extrusive igneous rock with amygdaloidal infilling

Fossilized Bone

Fossilized vertebrate bone

Granite

Granite

Fossilized Ammonite Fragment

Ammonoidea

Quartz Druzy

Silicon Dioxide (SiO2)

Jasper

Silicon dioxide (SiO2)

Granite

Felsic intrusive igneous rock

Mixed Rock Assortment

Polylithic geological specimens

Granite / Quartzite Specimen

Granite / Quartz (SiO2 with Feldspar and Mica)

Gneiss

Gneiss (Metamorphic Rock)

Biotite-bearing granite

Granite, composed chiefly of quartz, feldspar, and biotite; exact identification is uncertain from the photo.

Rounded quartz-rich river pebble

Likely quartz-bearing rock; exact lithology cannot be determined from the photograph

Granite

Intrusive Igneous Rock

Breciated Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Orbicular granite (likely rapakivi-type granite)

Granite; chiefly quartz, alkali feldspar, plagioclase, and biotite/hornblende

Quartz Pebble

Silicon Dioxide (SiO2)

Carnelian agate

Cryptocrystalline quartz (SiO₂), iron-oxide-bearing chalcedony

Granite with Mineral Vein

Plutonic Igneous Rock

Quartz-rich rock, possibly milky quartz

Quartz (SiO₂), likely a massive quartz specimen; exact identification is uncertain from the image

Milky quartz in a light-colored host rock

Quartz (SiO₂), likely with feldspar-rich matrix; exact host rock is unclear from the photo

Quartz Vein in Host Rock

Silicon Dioxide (SiO2) within metamorphic/igneous matrix

Small brown mineral fragment (undetermined)

Unidentified; image detail is insufficient for a reliable species identification

Granite

Granite, a felsic intrusive igneous rock composed chiefly of quartz, feldspar, and mica

Sandstone (with Iron Staining)

Clastic sedimentary rock (SiO2 with Fe2O3 oxides)

Granitic Gneiss

Gneiss (Metamorphic Rock)

Sandstone

Sedimentary Rock (Quartz Sandstone)

Iron-stained milky quartz vein

Quartz (SiO₂), with reddish iron-oxide staining, likely hematite or goethite

Likely garnet-bearing rock (possibly almandine garnet in matrix)

Garnet, likely almandine (Fe₃Al₂Si₃O₁₂); host rock cannot be determined from the image

Quartz geode fragment

Quartz (SiO₂), lining a cavity in a silica-rich rock

Likely serpentine

Serpentine-group minerals, chiefly antigorite, lizardite, or chrysotile; approximate formula Mg₃Si₂O₅(OH)₄

Quartz (or Chert/Flint)

Silicon Dioxide (SiO2)

Granite

Intrusive igneous rock

Sandstone with Quartz Vein

Arenite with Crystalline Silica (SiO2)

Painted Rock / Geode Specimen

Silicon Dioxide with artificial pigment coating

Weathered quartz-rich pebble

Likely milky quartz (SiO₂), possibly a quartz-rich vein fragment

Likely greenstone (altered basalt)

Chlorite–actinolite-bearing metabasalt; identification is tentative from the image

Sandstone

Clastic Sedimentary Rock

Granodiorite

Granodiorite (Intermediate intrusive igneous rock)

Dendritic Limestone

Limestone with manganese oxide dendrites, CaCO3

Granitic Pegmatite

Pegmatite

Mixed Mineral Assortment (Pyrite, Kyanite, Agate, Jasper)

FeS2 (Pyrite), Al2SiO5 (Kyanite), SiO2 (Agate/Jasper)

Mixed rough mineral specimens, likely quartz-bearing rocks

Probable quartz (SiO₂), with possible feldspar, iron oxides, and altered host rock