Sedimentary Rock (Metamorphosed)

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)

Sandstone (likely Graywacke or Lithic Sandstone)

Arenite / Wacke (SiO2 based with lithic fragments)

White Agate (Chalcedony)

Silicon Dioxide (SiO2)

Gneiss (River Cobble)

Gneiss (Foliated Metamorphic Rock)

Gneiss

Gneiss (High-grade Metamorphic Rock)

Gneiss

Gneiss (High-grade metamorphic rock)

Chert (specifically Flint or Dark Chalcedony)

Silicon Dioxide (SiO2)

Sedimentary Sandstone (Sandstone Slab)

Arenite (SiO2 with Fe2O3 staining)

Sandstone (Quartzose Sandstone)

Arenite (composed primarily of SiO2)

Sandstone

Arenite

Quartz Geode

Crystalline Silicon Dioxide (SiO2) in Geode form

Chert (Flint Nodules)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Red Jasper

Chalcedony (SiO2 with iron oxide impurities)

Chert (often called Jasper or River Siltstone)

Microcrystalline Quartz (SiO2)

Chert (varietal Chalcedony or Flint)

Silicon dioxide (SiO2) - Microcrystalline Quartz

Chert (Flint Nodules)

Microcrystalline or Cryptocrystalline Quartz (SiO2)