Red Sandstone
Arenite (Ferruginous Sandstone)
sedimentary
Category
Mineral (Sedimentary Context)
Browse mineral (sedimentary context) specimens identified by the Rock Identifier community.
Sandstone (Banded)
Clastic Sedimentary Rock (primarily SiO2)
sedimentary
Red Sandstone
Arenite (Ferruginous Sandstone)
sedimentary
Greywacke (River Pebble with Quartz Veins)
Greywacke (Indurated Sandstone); Veins: SiO2 (Quartz)
sedimentary
Septarian Nodule (Dragon Stone)
Septarian concretion (composition: Calcium Carbonate / Calcite, Aragonite, and Limestone/Clay)
sedimentary
Sandstone (specifically Banded Sandstone)
Clastic sedimentary rock (primarily SiO2)
sedimentary
Agate (specifically Waterline or Onyx-type Agate)
Silicon Dioxide (SiO2) - variety Chalcedony
mineral
Gneiss
Foliated Metamorphic Rock (Gneiss)
metamorphic
Dalmatian Stone (often misnamed Dalmatian Jasper)
Aplite (with hornblende/arfvedsonite inclusions)
igneous
Travertine (Tufa)
Terrestrial Sedimentary Limestone (CaCO3)
sedimentary
Sandstone
Arenite
sedimentary
Yellow Chalcedony (common opal or chert variant)
Silicon Dioxide (SiO2)
sedimentary (mineraloid/microcrystalline quartz)
Boulder Opal
Precious Opal in Ironstone (Amorphous Hydrated Silica, SiO2·nH2O)
Mineral
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Chalcedony (Quartz Nodule)
Silicon Dioxide (SiO2)
mineral
Yellow Chalcedony (Agate Pebble)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
mineral
Carnelian Agate
Silicon Dioxide (SiO2) - Carnelian variety of Chalcedony
mineral
Quartz Pebble (Chert/Chalcedony)
Silicon Dioxide (SiO2)
mineral
River Chalcedony / Agate
Chalcedony (Silicon Dioxide, SiO2)
mineral
Clear Quartz Crystal
Quartz (Silicon Dioxide, SiO2)
mineral
Blue Chalcedony
Microcrystalline Quartz (SiO2)
mineral
Red Jasper
Jasper (Silicon Dioxide, SiO2 with Fe2O3 inclusions)
mineral
Carnelian Agate
Carnelian (Silicon Dioxide - SiO2)
mineral
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Chalcedony (Agate/Chert variety)
Silicon Dioxide (SiO₂)
mineral
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
mineral
Jasper
Silicon Dioxide (SiO2)
mineral
Quartz (Peach/Orange variety)
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Pyrite (on the right) and Magnetite or Hematite (on the left)
Iron Sulfide (FeS2) and Iron Oxide (Fe3O4 or Fe2O3)
mineral
Yellow Chalcedony (Agate)
Silicon Dioxide (SiO2)
mineral
Gold Nugget
Native Gold (Au)
mineral
Specular Hematite Geode/Nodule
Specularite (Polycrystalline Hematite), Fe2O3
mineral
White Agate (Chalcedony)
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Agate (Chalcedony)
Cryptocrystalline Silica or Silicon Dioxide (SiO2)
mineral
Carnelian Agate
Carnelian (Silicon Dioxide - SiO2)
mineral
Clear Quartz Crystal Cluster
Silicon Dioxide (SiO2)
mineral
Ferruginous Quartz
Silicon Dioxide (SiO2) with iron oxide inclusions
mineral
Clear Quartz (Rock Crystal Fragments)
Silicon Dioxide (SiO2)
mineral
Calcite
Calcium Carbonate (CaCO3)
mineral
Agate
Agate (Silicon Dioxide - SiO2)
mineral