Sedimentary Rock (Metamorphosed)

Sandstone (Ferruginous)

Arenite (composed primarily of SiO2 with Fe2O3 cement)

Garnet Schist

Garnet-bearing Mica Schist (variety of compositions, often Al2SiO5 with X3Y2(SiO4)3)

Chalcedony (Botryoidal)

Silicon Dioxide (SiO2)

Turquoise

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

Chert (or Flint)

Silicon dioxide (SiO2)

Gneiss

Gneiss (High-grade metamorphic rock)

Sparkling Druzy Quartz on Matrix

Silicon Dioxide (SiO2) with iron oxide inclusions

Granite Cobble

Phaneritic Felsic Igneous Rock (Granite)

Sandstone

Arenite (composed primarily of SiO2)

Ironstone Concretion / Goethite Nodules

Ironstone (composed primarily of Goethite FeO(OH) and Limonite)

Chert (Jasper/Quartzite variety)

Microcrystalline Silica (SiO2)

Ironstone Concretion / Goethite-Hematite Nodule

Goethite/Hematite (α-FeO(OH) / Fe2O3)

Chert (and its variety Flint)

Silicon dioxide (SiO2) / Microcrystalline quartz

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Red Jasper

Jasper (SiO2) with Hematite (Fe2O3) inclusions

Ironstone Concretion (Boji Stone/Moqui Marble type)

Goethite/Hematite-encrusted Sandstone Concretion

Chert (Jasper variety)

Cryptocrystalline quartz (SiO2)

Tree Agate

Dendritic Chalcedony (SiO2)

Chert (Flint nodule)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chert (Green variety)

Silicon Dioxide (SiO2)

Geode with Quartz/Chalcedony

Silicon Dioxide (SiO2)

Chert (Tan/Grey variety)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Yellow Jasper

Silicon Dioxide (SiO2) with iron inclusions

Shale with Pyrite

Clastic sedimentary rock containing Iron Disulfide (FeS2)

Siltstone/Sandstone (possibly Wonderstone or Picture Sandstone)

Clastic Sedimentary Rock (primarily SiO2 with Iron Oxide inclusions)

Sandstone (Banded)

Clastic Sedimentary Rock (primarily SiO2 with Iron Oxide staining)

Quartz Druzy Geode Fragment

Silicon Dioxide (SiO2)

Chert Pebble/Nodule

Chert (a microcrystalline or cryptocrystalline sedimentary form of quartz, SiO2)

Geode (unopened)

Chert / Chalcedony Geode (SiO2)

Chert (specifically Flint or Jasper-Chert)

Silicon Dioxide (SiO2)

Dyed Agate Slice

Silicon Dioxide (SiO2) with artificial colorants

Chert (specifically Jasper/Brown Chert)

Silicon Dioxide (SiO2)

Kambaba Jasper (Crocodile Jasper)

Stromatolitic Rhyolite/Jasper (SiO2)

Picture Jasper

Silicon dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Chert (Flint Nobule)

Silicon Dioxide (SiO2)

Herkimer Diamond (Quartz)

Silicon Dioxide (SiO2)

Agate (Carnelian / Chalcedony)

Silicon Dioxide (SiO2)

Chert (Jasper and Chalcedony)

Silicon Dioxide (SiO2)

Black Jasper (Black Onyx substitute)

Silicon Dioxide (SiO2) with carbonaceous impurities

Quartz Druze on Matrix

Silicon Dioxide (SiO2)

Magnetite

Magnetite (Fe3O4)