Stromatolite
Laminated biogenic sedimentary structure (formed by Cyanobacteria)
sedimentary
Category
Sedimentary (Biogenic Sediment Or Biological Remain)
Browse sedimentary (biogenic sediment or biological remain) specimens identified by the Rock Identifier community.
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Polished iron-stained chert or jasper pebble
Microcrystalline quartz (SiO₂), likely ferruginous chert/jasper
sedimentary
Polished fossilized wood
Silicified wood (petrified wood), commonly quartz/chalcedony replacing wood
fossil
Fossiliferous Limestone with Rugose Coral
Calcite (CaCO3) containing a Rugosa (Horn Coral) fossil
sedimentary
Coquina
Biogenic calcarenite / Coquina (CaCO3)
sedimentary
Coquina
Coquina (Biogenic Limestone / CaCO3)
sedimentary
Coquina
Biogenic Limestone (Calcitic shells)
sedimentary
Coquina
Biogenic Limestone (Calcite, CaCO3)
sedimentary
Coquina
Biogenic Limestone (Calcite/Aragonite)
sedimentary
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
sedimentary
Raw Agate (Chalcedony Nodule)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
mineral
Chert (Nodule)
Microcrystalline or cryptocrystalline Quartz (SiO2)
sedimentary
Chert (Flint/Jasper)
Silicon Dioxide (SiO2)
sedimentary
Limestone (Elephant Skin or Karst-weathered)
Calcium Carbonate (CaCO3)
sedimentary
Silicified Snail Fossil
Gastropod (likely replaced by Chalcedony/Quartz - SiO2)
fossil
Ironstone Concretion (Limonite/Goethite)
Ironstone (composed primarily of Goethite FeO(OH) and Limonite)
sedimentary
Fossilized coral (likely tabulate or colonial coral)
Fossil coral; possibly Hexagonaria or related Paleozoic colonial coral
fossil
Fossilized Coral (Petrified Coral)
Lithostrotionella (example genus) / Scleractinia
fossil
Petrified Wood
Silicified Wood (SiO2)
mineral
Pyrite in Matrix
Iron Sulfide (FeS2)
mineral
Optical Calcite
Calcite (Calcium Carbonate, CaCO3)
mineral
Chert / Jasper Pebble
Microcrystalline Quartz (SiO2)
sedimentary
Coquina or Fossilized Shell Fragment
Calcium Carbonate (CaCO3) / Biogenic Limestone
sedimentary
Fossilized Tiger Shark Tooth
Galeocerdo cuvier (fossilized hydroxylapatite)
sedimentary
Chert (Flint / Jasper / Hornstone)
Microcrystalline Quartz (SiO2)
sedimentary
Green Chert (Jasper / Flint)
Silicon Dioxide (SiO2)
sedimentary
Chert
Chert (Microcrystalline Quartz, SiO2)
sedimentary
Breccia
Clastic Breccia (SiO2/CaCO3 dominated)
sedimentary
Fossiliferous Limestone
Biogenic Sedimentary Rock (primarily CaCO3 with fossil fragments)
sedimentary
Tumbled fossiliferous limestone
Bioclastic limestone, chiefly calcite (CaCO₃), with fossil shell fragments
fossil
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
mineral
Likely weathered petrified wood
Silicified wood, chiefly microcrystalline quartz (SiO₂) replacing wood tissue
fossil
Limestone with Lichen
Carbonate Sedimentary Rock (primarily CaCO3)
sedimentary
Chert
Silicon dioxide (SiO2)
sedimentary
Calcite in Matrix
Calcium Carbonate (CaCO3)
mineral
Shark Tooth Fossil
Carcharhiniformes or Lamniformes (order level fossil)
fossil
Fossiliferous Limestone
Calcium Carbonate (CaCO3) with Biogenic Inclusions
sedimentary
Fossil shark teeth
Likely fossilized shark teeth, possibly Carcharhiniformes or related sharks; exact species cannot be determined from the photo.
fossil
Limestone (containing Fossil Mold)
Sedimentary Calcium Carbonate (CaCO3)
sedimentary
Boxwork Siderite or Sepatarian Nodule Weathering
Siderite (FeCO3) with secondary mineralization or Boxwork Geode fragment
sedimentary
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
mineral
Mossy Rock
Mixed lithology rock with Bryophyta (moss)
sedimentary