Agate
Silicon dioxide (Chalcedony), SiO2
Category
Browse sedimentary rock (possibly conglomerate or breccia with a quartz vein) specimens identified by the Rock Identifier community.
Agate
Silicon dioxide (Chalcedony), SiO2
Epidote
Epidote (Ca2(Al, Fe)3(SiO4)3(OH))
Quartz / Chalcedony Geode Fragment
Silicon Dioxide (SiO2)
Ferruginous Sandstone (Ironstone)
Sandstone with Hematite/Goethite cement (SiO2 + FeO(OH))
Milky Quartz Pebble
Quartz (SiO2)
Clear Quartz (Crystal Quartz)
Silicon Dioxide (SiO2)
Quartz Geode
Silicon Dioxide (SiO2)
Clear Quartz Geode
Crystalline Silicon Dioxide (SiO2)
Sandstone (Ferruginous)
Clastic sedimentary rock (primarily SiO2 with Fe2O3)
White Quartz
Silicon Dioxide (SiO2)
Chalcedony Geode Fragment
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Agate
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Jasper
Microcrystalline Quartz (SiO2)
Bull Quartz
Quartz (Silicon Dioxide, SiO2)
Quartz (Clear Quartz Point)
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Rose Quartz
Silicon dioxide with traces of titanium, iron, or manganese (SiO2)
Geode (unopened)
Quartz-filled Geode (SiO2)
Tumbled Quartz
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2) with host rock matrix
Milky Quartz
Silicon Dioxide (SiO2)
Sandstone with Dendritic Inclusions
Quartzose Sandstone
Chert (Flint)
Microcrystalline Quartz (SiO2)
Milky quartz with dark host-rock inclusions
Quartz (SiO₂), likely in a granitic or metamorphic matrix
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
River Stone (Quartzite/Chert)
Metamorphosed Quartz-rich Sedimentary Rock
River Cobbles (Quartzite and Sandstone)
Metamorphosed Quartz-rich Sedimentary Rock
Jasper and Agate Mix
Silicon dioxide (SiO2) - Microcrystalline Quartz
Quartzite (clastic/metamorphic subtype)
Quartzite (primarily Silicon Dioxide, SiO2)
Lemon Quartz (or Yellow Calcite)
Silicon Dioxide (SiO2) / Calcium Carbonate (CaCO3)
Jasper Pebble
Microcrystalline Quartz (SiO2)
River Stone (Quartzite/Chert mixture)
Microcrystalline Quartz (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Chert (or Flint)
SiO2 (Microcrystalline Quartz)
Quartz (Milky or Common Quartz)
Silicon Dioxide (SiO2)
Sandstone with Manganese Dendrites
Clastic Sedimentary Rock (SiO2 based with MnO2 inclusions)
Chert
Microcrystalline Quartz (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Sandstone
Sedimentary Rock (Quartz arenite/Arkosic sandstone)
Green Jasper Pebble
Microcrystalline Quartz (SiO2) with impurities
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Quartz Geode
Silicon Dioxide (SiO2) in Geode form