Sedimentary Rock (Altered)

Quartz Geode

Silicon Dioxide (SiO2)

Agate

Silicon Dioxide (SiO2)

Yellow Quartz (Chalcedony or Agate)

Silicon Dioxide (SiO2)

Quartz Geode / Druzy Quartz

Silicon Dioxide (SiO2)

Crazy Lace Agate

Silicon Dioxide (SiO2) with iron and aluminum inclusions

Dyed Blue Agate

Silicon Dioxide (SiO2)

Moss Agate

Chalcedony (Silicon Dioxide, SiO2) with inclusions

Clear Quartz

Silicon Dioxide (SiO2) / Rock Crystal

Gneiss

Gneiss (High-grade metamorphic rock)

Limestone with Calcite Veins

Sedimentary Calcium Carbonate (CaCO3)

Jasper (Chert)

Silicon Dioxide (SiO2)

Quartz Pebble (Geode-like)

Silicon Dioxide (SiO2)

Sandstone (Muddy/Silty Variety)

Arenite with high silt/clay content (clastic sedimentary rock)

Dalmatian Stone (often called Dalmatian Jasper)

Peralkaline Quartz-Feldspar Rock with Arfvedsonite (formerly believed to be Jasper)

Petrified Wood

Silicified Wood (primarily Quartz / Chalcedony: SiO2)

Gneiss

Gneiss (High-grade regional metamorphic rock)

Septarian Nodule

Septarian Concretion (CaCO3 with Siderite/Limonite streaks)

Petoskey Stone

Hexagonaria percarinata

Jasper (Multi-color Chert)

Silicon dioxide (SiO2)

Jasper

Silicon dioxide (SiO2) with impurities

Quartzite

Quartzite (SiO2)

Brecciated Chert

Sedimentary Chert (SiO2) with Calc-Silicate mineralization

Clear Quartz Cluster

Silicon Dioxide (SiO2)

Carnelian Agate

Carnelian (SiO2 with iron oxide impurities)

Yellow Quartzite or Yellow Jasper

Quartzite (primarily SiO2 with Iron oxide staining)

Schist (Micaceous Schist)

Schist (comprising Muscovite/Biotite mica, Quartz, and Feldspar)

Sandstone with Ironstone Banding

Clastic Sandstone (composed of Quartz with Hematite/Limonite bonding)

Sandstone (Ferruginous)

Arenite (composed primarily of SiO2 with Fe2O3 cement)

Shale

Fissile Clay-dominant Mudrock (SiO2, Al2O3, K2O, Na2O, CaO, MgO)

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Red Jasper

Silicon Dioxide (SiO2) with Hematite impurities

Red Jasper

Jasper (Silica/Silicon Dioxide, SiO2 plus iron inclusions)

Jasper with Quartz Druzy

Silicon Dioxide (SiO2)

Chert Nodule

Chert (Cryptocrystalline variety of Quartz, SiO2)

Druzy Quartz Geode (likely Smokey Quartz variety)

Silicon Dioxide (SiO2) - specifically a geode formation lined with druzy quartz crystals, with a likely brownish hue indicating smokey quartz.

Gneiss

Gneiss (High-grade Metamorphic Rock)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Quartz Geode in Sedimentary Matrix

Silicon Dioxide (SiO2) within a limestone/dolostone host

Limestone (Weathered)

Calcium Carbonate (CaCO3)

Jasper Agate (specifically Brecciated Jasper)

Silicon Dioxide (SiO2) with iron oxide and clay impurities

Quartzite Pebble (River Rock)

Quartzite (mainly SiO2)