Mineral On Sedimentary Rock

Quartzite Pebble

Metamorphosed Quartz Sandstone (SiO2)

Yellow Agate

Chalcedony (cryptocrystalline silica), SiO2

Amethyst Geode

Amethyst (Silicon Dioxide), Formula: SiO2

Quartz with Chalcopyrite and Pyrite

Silicon Dioxide (SiO2) with Copper Iron Sulfide (CuFeS2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Ferruginous Quartz

Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions

Quartz (likely)

Quartz (SiO2 - Silicon Dioxide)

Banded Chert or Chert with Quartz Veins

Chert (SiO2)

Dendritic Agate or Manganese Nodule in Chert/Limestone

Silicon Dioxide (SiO2) with Manganese Oxide (MnO2) inclusions

Coral Rock (Coquina)

Biogenic Limestone (Calcium Carbonate - CaCO3)

Quartz Geode

Silicon Dioxide (SiO2)

Yellow Quartz Pebble

Silicon Dioxide (SiO2)

Basalt

Mafic volcanic rock (various silicate minerals including Pyroxene and Plagioclase)

Orange Quartzite (Tumbled)

Quartzite (SiO2)

Grass (Organic Matter/Soil)

Poaceae (family of monocotyledonous flowering plants)

Unakite

Epidotized Granite

Note regarding baguette production (not a rock)

Digital text image - Somali language

Granite

Phaneritic Plutonic Felsic Rock

Basalt with Quartz/Feldspar Vein

Amygdaloidal Basalt with Plutonic intrusion (SiO2/KAlSi3O8)

Yellow Calcite

Calcium Carbonate (CaCO3)

Selenite (Satin Spar)

Gypsum (CaSO4·2H2O)

Botryoidal Pyrite

Iron Sulfide (FeS2)

Schist

Mica Schist

Iron-Stained Quartz (Riverside Cobble)

Silicon Dioxide (SiO2) with Limonite/Hematite inclusions

Lapis Lazuli

Complex mixture of minerals (lazurite, calcite, pyrite, and sodalite); (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2

Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Tiger's Eye

Pseudomorph of Crocidolite (SiO2 with iron oxides)

Gemstone Sand (Mineral Assortment)

Mixed Mineral Concentrates (Commonly including Quartz SiO2, Garnet X3Y2(SiO4)3, and Tourmaline (Na,Ca)(Li,Mg,Al)3(Al,Fe,Mn)6(BO3)3(Si6O18)(OH,F)4)

Chert

Chert (microcrystalline quartz, SiO2)

Quartzite Pebble (River Rock)

Metamorphic Quartzite (predominantly SiO2)

Bumblebee Jasper

Calcite with Arsenic and Manganese oxides (technically a volcanic rock)

Petoskey Stone

Hexagonaria percarinata (Fossilized Rugose Coral)

Marble

Recrystallized Calcite (CaCO3)

Quartz / River Cobble

Silicon Dioxide (SiO2)

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Druzy Quartz on Host Rock

Silicon Dioxide (SiO2)

Blue Calcite

Calcium Carbonate (CaCO3)

Quartz Pebble

Silicon Dioxide (SiO2)

Demitasse Granite (Diorite-Granite transition)

Intermediate Plutonic Rock (Granodiorite/Diorite mix)

Chert (Arrowhead or Projectile Point)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)