Not A Rock

Bivalve Fossil (Clam)

Class Bivalvia (Calcium Carbonate, CaCO3)

Chert (Gravel Bit)

Microcrystalline silica (SiO2)

White Quartz Pebble

Silicon Dioxide (SiO2)

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

Amygdaloidal Basalt

Amygdaloidal Basalt (with secondary mineral infilling)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Chert (varieties include Flint and Jasper)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Quartz Vein / Milky Quartz

Silicon Dioxide (SiO2)

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Conglomerate

Conglomerate (Sedimentary rock containing rounded clasts)

Amethyst (Tumbled)

Purple Quartz (SiO2 with iron impurities and irradiation)

Petrified Wood

Silicified Wood (primarily SiO2)

Petrified Wood

Silicified Wood (primarily SiO2 - Silicon Dioxide)

Quartz Vein in Schist

Quartz (SiO2) in Mica Schist

Ferruginous Quartz

Silicon Dioxide (SiO2) with Limonite/Hematite inclusions

Mookaite Jasper

Radiolarite (SiO2 with impurities)

Sandstone (Quartzose)

Arenite (primarily SiO2)

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

Milky Quartz

Crystalline Silicon Dioxide (SiO2)

Amphibolite with Hornblende

Amphibole-rich Metamorphic Rock (Ca2(Mg,Fe)5Si8O22(OH)2)

Black Tourmaline in Quartz

Schorl (NaFe3Al6(BO3)3Si6O18(OH)4) in Silicon Dioxide (SiO2)

Chert (often called Flint or Jasper)

Silicon Dioxide (SiO2)

Scoria (Lava Rock)

Vesicular Basalt / Scoria

Granite

Plutonic felsic igneous rock

Granite

Granite (Phaneritic Igneous Rock)

Sandstone

Arenite (Clastic Sedimentary Rock)

Andesite

Andesite (Intermediate Volcanic Rock)

Pink Granite

Granite (Phaneritic intrusive rock)

Andesite

Andesite (Intermediate Volcanic Rock)

Eclogite

Eclogite (Omphacite + Almandine-Pyrope Garnet)

Sandstone (Greywacke/Lithic Sandstone)

Arenite (composed primarily of SiO2)

Granite

Phaneritic Igneous Rock (primarily Quartz, Feldspar, and Mica)

Granite

Phaneritic Igneous Rock (primarily Quartz, Feldspar, and Mica)

Basalt with Quartz Veins

Amygdaloidal Basalt (matrix) with Crystalline SiO2 (veins)

Granite

Granite (Felsic Plutonic Rock)

Basalt

Basalt (Mafic volcanic rock)

Garnet Schist or Garnet-bearing Quartzite

Metamorphic rock containing Almandine Garnet (Fe3Al2(SiO4)3) and Quartz (SiO2)

Chert (Quartz Variety)

Chert (mostly SiO2 / Silicon Dioxide)

Felsic Igneous Rock (likely Rhyolite or weathered Granite)

Felsic Volcanic/Plutonic Rock

Druzy Quartz (on Quartzite or Chert)

Silicon Dioxide (SiO2)

Turquoise in Matrix

Hydrated phosphate of copper and aluminum (CuAl6(PO4)4(OH)8·4H2O)

Quartz in Matrix (possibly with Biotite or Hornblende)

Quartz (Silicon Dioxide, SiO2) in Granitic Matrix