Ambergris
Ambrein-rich Calculus
Organic (Pseudo-geological)
Category
Organic (Pseudo Geological)
Browse organic (pseudo geological) specimens identified by the Rock Identifier community.
Ferruginous Sandstone Concretion (Ironstone Phosphorite)
Ferruginous Sandstone (variable Fe-oxide/hydroxide composition)
sedimentary
Banded Sedimentary Rock (Siltstone/Mudstone with concretion)
Siltstone with Ferruginous Banding
sedimentary
Ironstone Concretion
Ironstone (primarily Siderite or Limonite)
sedimentary
Aragonite (Star Cluster or Twinned variety)
Aragonite (Calcium Carbonate, CaCO3)
mineral
Aragonite
Aragonite (CaCO3)
mineral
Aragonite
Aragonite (Carbonate mineral), CaCO3
mineral
Azurite in Gossan
Azurite (Cu3(CO3)2(OH)2) in Limonite/Goethite matrix
mineral
Iron Slag
Anthropogenic Ferro-silicate
mineral
Fairy Stone (Staurolite Twin)
Staurolite (Fe,Mg,Zn)2Al9Si4O22(OH)2
metamorphic
Concrete fragment with Aggregate
Anthropogenic Concrete with Calcarious and Siliceous Aggregate
sedimentary (anthropogenic/man-made)
Aragonite Star Cluster
Aragonite (Calcium Carbonate, CaCO3)
mineral
Aragonite Star Cluster
Aragonite (Calcium Carbonate, CaCO3)
mineral
Staurolite (Fairy Stone)
Staurolite (Fe2+2Al9Si4O23(OH))
metamorphic
Arsenopyrite
Arsenopyrite (FeAsS)
mineral
Aragonite Star Cluster
Aragonite (Calcium Carbonate - CaCO3)
mineral
Staurolite (Fairy Stone)
Staurolite (formula: Fe2+2Al9Si4O23(OH))
metamorphic
Aragonite Star Cluster
Aragonite (CaCO3)
mineral
Aragonite Star Cluster
Aragonite (Sputnik habit) - CaesarCO3
mineral
Staurolite (Fairy Cross)
Staurolite (Fe2+2Al9Si4O23(OH))
metamorphic
Aragonite Star Cluster
Aragonite (Calcium Carbonate, CaCO3)
mineral
Serpentine (rough serpentine-rich rock)
Serpentine-group minerals, chiefly antigorite and/or lizardite; composition broadly Mg₃Si₂O₅(OH)₄
metamorphic
Aragonite
Aragonite (CaCO3)
mineral
Biotite (Mica)
Biotite group (K(Mg,Fe)3AlSi3O10(F,OH)2)
mineral
Staurolite (Fairy Cross)
Staurolite (Fe2+2Al9Si4O23(OH))
metamorphic
Pyrite (Limonite Pseudo-morph after Pyrite)
Iron sulfide (FeS2) transitioning to Iron oxide-hydroxide (FeO(OH)·nH2O)
mineral
Polished septarian-style jasper or rhyolite
Likely silica-rich volcanic rock, possibly rhyolite, with iron-oxide and manganese-oxide veining
igneous
Alexandrite in Matrix
Chrysoberyl (BeAl2O4 with Chromium impurities)
mineral
Greenschist (or Serpentinite with Manganese Dendrites)
Greenschist facies metamorphic rock
metamorphic
Aragonite
Aragonite (CaCO3)
mineral
Ironstone Concretion / Goethite Nodules
Ironstone (composed primarily of Goethite FeO(OH) and Limonite)
sedimentary
Red Tiger's Eye
Silicified Crocidolite (Quartz pseudo-morph after Crocidolite), SiO2
metamorphic
Biotite Mica
Biotite, K(Mg,Fe)3AlSi3O10(F,OH)2
mineral
Kidney Stone
Nephrolithiasis (Calcium Oxalate, Hydroxyapatite, or Uric Acid)
mineral
Pearl (in Marcasite Jewelry)
Biogenic Calcium Carbonate (primarily Aragonite, CaCO3)
gemstone
Quartz pebble or seed/crumb
SiO2 (if quartz)
mineral
Fossilized bone fragment
Fossil bone, composed chiefly of carbonate-fluorapatite (bioapatite)
fossil
Soil Aggregates
Pedological aggregates (Unconsolidated regolith)
sedimentary
Horse Chestnut (Buckeye seed)
Aesculus hippocastanum seed
Organic (Non-geological)
Soil with Mineral Detritus and Quartz Fragments
Regolith / Silicate Mineral Aggregate
sedimentary
Black Pearl (Tahitian Pearl)
Aragonite / Calcite (CaCO3) with Conchiolin
mineral
Red Coral
Corallium rubrum (Calcium Carbonate, CaCO3 with Carotenoid pigments)
Mineraloid (Organic Gemstone)