Sedimentary Rock (Altered)

Jasper (Iron-stained Chert)

Silicon Dioxide (SiO2) with iron oxide inclusions

Fossilized Crinoid Stem

Class Crinoidea (Echinodermata)

Limestone (Porous/Travertine variant)

Sedimentary Calcium Carbonate (CaCO3)

Concrete Paver (Artificial Cementitious Rock)

Hydrated Portland Cement Aggregate

Jasper with Quartz Vein

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Yellow Jasper (Iron-stained Quartz)

Jasper (Silicon Dioxide, SiO2 plus iron oxide impurities)

Quartz Druze on Matrix

Silicon Dioxide (SiO2)

Fossilized Bone Fragment

Permineralized Vertebrate Bone (Hydrox yapatite replaced by Silica or Calcite)

Mica Schist with Pyrite

Muscovite/Biotite Schist with Iron Sulfide (FeS2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Bumblebee Jasper

Calcite-Auripigment-Pyrite-Realgar assemblage (Carbonate/Sulphide mixture)

Banded Gneiss (River Cobble)

Gneiss (a high-grade metamorphic rock)

Quartz

Quartz (SiO2)

Favosites Fossil (Honeycomb Coral)

Favosites sp. (Extinct genus of tabulate coral)

Pink Opal

Hydrated Amorphous Silica (SiO2·nH2O)

Opal

Hydrated Amorphous Silica (SiO2·nH2O)

Halite (Rock Salt)

Halite (Sodium Chloride, NaCl)

Rock Salt (Halite)

Halite (Sodium Chloride, NaCl)

Banded Gneiss

Gneiss (High-grade regional metamorphic rock)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Banded Chert or Chert with Quartz Veins

Chert (SiO2)

Rough Emerald

Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)

Laterite

Laterite (no specific mineral formula as it's a rock type)

Coral Rock (Coquina)

Biogenic Limestone (Calcium Carbonate - CaCO3)

Orange Quartzite (Tumbled)

Quartzite (SiO2)

Quartz (Milky or Cloudy Quartz)

Silicon Dioxide (SiO2)

Quartzite Pebble (River Rock)

Metamorphic Quartzite (predominantly SiO2)

Chert

Chert (microcrystalline quartz, SiO2)

Bumblebee Jasper

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

Petoskey Stone

Hexagonaria percarinata (Fossilized Rugose Coral)

Granitic Gneiss

Gneiss (High-grade regional metamorphic rock)

Yellow Quartz (Citrine/Yellow Jasper mix)

Silicon Dioxide (SiO2)

Druzy Quartz (on Geode Fragment)

Silicon Dioxide (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Grooved Maun Ball (Maul/Hammerstone-like Concretion)

Calcareous/Ferruginous Concretion in Sandstone Matrix

Chert (Arrowhead or Projectile Point)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Jasper

Silicon dioxide (SiO2)

Red Jasper (specifically Brecciated Jasper)

Silicon Dioxide (SiO2) with Hematite inclusions

Red Sandstone

Arenite (primarily SiO2 with hematite/iron oxide coating)

Jasper with Quartz Veining

Silicon Dioxide (SiO2) with impurities

Sandstone with Liesegang Rings

Arenite with Iron Oxide Liesegang Banding

Chert (varietal Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)