Devil's Toenail
Gryphaea (extinct genus of foam oysters, typically composed of Calcite CaCO3)
sedimentary
Category
Sedimentary (Biogenic Sediment Or Biological Remain)
Browse sedimentary (biogenic sediment or biological remain) specimens identified by the Rock Identifier community.
Fossiliferous Limestone (Gritstone/Marl)
CaCO3 (Calcium Carbonate) with Fossil Inclusions
sedimentary
Sandstone concretion (Ironstone-stained)
Arenite with Limonite/Hematite staining (Silica-based with Iron Oxides)
sedimentary
Fossilized Crinoid Stem
Class Crinoidea (Echinodermata)
sedimentary
Fossil Shark Tooth (Otodus obliquus)
Otodus obliquus; hydroxyapatite (mineralized form Ca5(PO4)3(OH))
sedimentary (fossiliferous)
Shell Cameo
Cypraecassis rufa (Bullmouth Queen Helmet Shell)
mineraloid / biogenic specimen
Fossilized Oyster Shell
Gryphaea or Crassostrea fossil (Calcium Carbonate, CaCO3)
sedimentary
Chert (containing fossil leaf impression)
Microcrystalline silicon dioxide (SiO2)
sedimentary
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
mineral
Fossiliferous Sandstone (with Brachiopod or Bivalve mold)
Clastic Sedimentary Rock with Macrofossil Mold
sedimentary
Fossiliferous Limestone (Coquina / Shell Limestone)
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Petrified Wood
Silicified wood (principally Silicon Dioxide, SiO2)
sedimentary
Petrified Wood
Silicified Wood (primarily SiO2)
sedimentary
Petrified Wood
Silicified Wood (primarily SiO2)
sedimentary
Fossiliferous Limestone
Limestone (CaCO3 - Calcium Carbonate)
sedimentary
Fossiliferous Limestone
Biogenic Calcium Carbonate (CaCO3)
sedimentary
Atlantic Calico Scallop (Biogenic Aragonite/Calcite)
Argopecten gibbus (Chemical: CaCO3)
mineral
Petrified Wood
Silicified Wood (primarily SiO2)
sedimentary
Conglomerate with Fossilized Shark Teeth
Clastic sedimentary rock (Conglomerate) containing Elasmobranchii remains
sedimentary
Tahitian Pearl
Biogenic Calcium Carbonate (Aragonite/Calcite), CaCO3
mineral
Pearl
Biogenic Calcium Carbonate (Aragonite and Conchiolin), CaCO3
mineral
Fossiliferous Limestone (Coquina)
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Fossilized Brachiopod
Phylum Brachiopoda (replaced by Calcite/CaCO3)
sedimentary
Amber
Succinurite (C10H16O)
mineraloid
Amber (Rough)
Amber (Fossilized Tree Resin, succinite)
mineral
Petrified Wood
Silicified Wood (SiO2)
Mineral / Fossil
Amber
Succinite (with approximate formula C10H16O)
mineraloid
Amber
Succinite (fossilized resin)
mineral
Amber
Succinite (organic fossilized resin)
mineraloid
Petrified Wood
Silicified Wood (primarily Quartz / Chalcedony: SiO2)
metamorphic
Amber
Succinite (specifically for Baltic amber); Complex mixture of organic compounds (C10H16O)
Organic Mineraloid
Sea Bean (Hamburger Bean)
Mucuna sloanei
organic/biological specimen
Fossilized Shark Teeth
Carcharhiniformes or Lamniformes species (common mineral: Fluorapatite/Ca5(PO4)3F)
sedimentary (fossilized organic matter)
Brachiopod Fossil (Spiriferid)
Order Spiriferida (Phylum Brachiopoda); mineralized as Calcite (CaCO3) or Chert (SiO2)
sedimentary (fossilized organic remain)
Chert (Jasper variation)
Microcrystalline Quartz (SiO2)
sedimentary
Coquina
Biogenic Limestone
sedimentary
Fossilized Shark Tooth (Cretaceous to Neogene)
Elasmobranchii dental fossil (likely Squalicorax or similar species)
mineral (biogenic replacement)
Amber
Succinite (Fossilized Tree Resin) - C10H16O
mineral
Sandstone (likely Quartzose type)
Clastic sedimentary rock (primarily SiO2)
sedimentary
Amber
Fossilized tree resin (not a true mineral as it is organic and amorphous); Chemical formula is highly variable, but often approximated as C10H16O.
Mineral
Brain Coral Fossil
Family Mussidae or Merulinidae (Order Scleractinia)
sedimentary
Chert (Chalcedony/Agate)
Microcrystalline Quartz (SiO2)
sedimentary