Beach Agate / Quartz Pebble
Silicon Dioxide (SiO2)
Category
Browse sedimentary (secondary mineral formation) specimens identified by the Rock Identifier community.
Beach Agate / Quartz Pebble
Silicon Dioxide (SiO2)
Yellow Chalcedony (Agate Pebble)
Silicon Dioxide (SiO2)
Carnelian
Carnelian (Cryptocrystalline Quartz, SiO2)
Turquoise
Turquoise (Hydrated phosphate of copper and aluminium), CuAl6(PO4)4(OH)8·4H2O
Turquoise (possible Dyed Howlite or Magnesite imitation)
CuAl6(PO4)4(OH)8·4H2O (Turquoise)
Turquoise
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Turquoise
Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]
Turquoise
CuAl6(PO4)4(OH)8·4H2O (Hydrated copper and aluminum phosphate)
Turquoise
Hydrate phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Turquoise in Matrix
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Quartz Geode
Silicon Dioxide (SiO2) within Sedimentary host rock
Green Calcite
Calcium Carbonate (CaCO3)
Chalcedony (Yellow/Honey variety)
Microcrystalline Quartz (SiO2)
Calcite
Calcium Carbonate (CaCO3)
Aragonite Star Cluster
Aragonite (Calcium Carbonate - CaCO3)
Limonite (Iron Stone/Iron Ore)
FeO(OH)·nH2O (Hydrous ferric oxide)
Ironstone concretion (possibly pyrite-bearing)
Iron-rich sedimentary concretion, likely composed of goethite/limonite with possible pyrite
Iron-rich rock, possibly hematite-rich ironstone
Likely hematite (Fe₂O₃) or a hematite-bearing ironstone; the photo is insufficient for a definitive identification
Generic Pebble / Rock Fragment
Lithic fragment / Weathered rock
Quartz Geode
Silicon Dioxide (SiO2) in a Secondary Sedimentary/Volcanic cavity
Sandstone
Arenite (primarily SiO2)
Green aventurine (likely quartzite)
Quartz-rich quartzite; predominantly SiO₂ with green mica/fuchsite or chlorite inclusions
Red Jasper
Silicon Dioxide with Hematite (SiO2 + Fe2O3)
Unidentified small brown rock
Undetermined; image does not show enough detail for reliable identification
Banded Jasper
Silicate Mineral (Microcrystalline Quartz / SiO2)
Dalmatian Jasper
Peralkaline Quartz-Feldspar Rock with Arfvedsonite
Gossan (with Limonite/Hematite coating)
Ferruginous Gossan (Fe2O3·nH2O / Fe2O3)
Quartz Geode
Silicon Dioxide (SiO2) in Geode formation
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily Quartz with Limonite/Goethite staining)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Limonite (Ironstone Concretion)
Limonite (Hydrous ferric oxide mixture, FeO(OH)·nH2O)
Limestone with Calcite Veining
Sedimentary Rock (Calcium Carbonate, CaCO3)
Possible fossil-bearing pebble
Unidentified fine-grained sedimentary rock; the small orange feature may be a fossil or mineral inclusion
Orange Calcite
Calcium Carbonate (CaCO3)
Quartz Geode
Silicon Dioxide (SiO2)
Turquoise
CuAl6(PO4)4(OH)8·4H2O (Hydrous phosphate of copper and aluminium)
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
Green Calcite
Calcium Carbonate (CaCO3)
Brecciated Chert
Sedimentary Chert (SiO2) with Calc-Silicate mineralization
Starfish Fossil
Asteroidea fossil
Yellow Jasper
Chalcedony (Silicon Dioxide with Iron inclusions), SiO2
White pebbles (rock material not identifiable from the image)
Undetermined; the smooth, pale pieces could be quartz, quartzite, or another light-colored rock