Chert (Flint)
Microcrystalline silica (SiO2)
sedimentary
Category
Mineral Like Biological Tissue
Browse mineral like biological tissue specimens identified by the Rock Identifier community.
Learn about Mineral Like Biological Tissue in the encyclopedia
View all →
Fossilized Coral
Anthozoa (Fossilized)
Sedimentary / Fossil
Chert / Jasper Pebble
Microcrystalline Quartz (SiO2)
sedimentary
Ironstone Concretion
Ironstone (Limonite/Goethite Concretion)
sedimentary
Amber
Succinite (C10H16O)
Mineraloid
Freshwater Pearl
Aragonite / Biogenic Calcium Carbonate (CaCO3)
mineral
Amber
Succinite (approximate formula C10H16O)
mineral
Shark Tooth Fossil
Otodus sp. (possibly Cretalamna)
fossil
Amber
Succinite (C10H16O)
mineral
Pink Aragonite
CaCO3
mineral
Polished septarian nodule
Calcite–aragonite–barite septarian concretion, commonly in a claystone or limestone matrix
sedimentary
Bivalve Fossil (Clam)
Class Bivalvia, likely Mercenaria or similar genus
fossil
Calcite
Calcium Carbonate (CaCO3)
mineral
Amber (in Matrix/Shale)
Amber (Fossilized Tree Resin)
mineral
Soil with Mineral Detritus and Quartz Fragments
Regolith / Silicate Mineral Aggregate
sedimentary
Pearl
Organic gemstone (Calcium carbonate - CaCO3)
mineral
Pearl
Calcium Carbonate (CaCO3) - Aragonite/Calcite organic gemstone
mineral
Pink Pearl
Calcium Carbonate (Aragonite/Calcite) with Conchiolin (CaCO3)
mineral
Pearl
Calcium Carbonate (CaCO3) + Conchiolin
mineral
Tufa (Calcareous Tufa)
Calcareous Tufa (Precipitated CaCO3)
sedimentary
Aragonite
Aragonite (Calcium Carbonate - CaCO3)
mineral
Amber
Succinite (Fossilized Tree Resin)
fossil
Chert
Channery Chert (Microcrystalline Quartz)
sedimentary
Obsidian
Obsidian (Volcanic Glass)
igneous
Fossilized bivalve shell
Bivalvia (likely a venerid or similar clam); shell composed mainly of CaCO₃ as aragonite/calcite
fossil
Fossilized Brachiopod
Phylum Brachiopoda (General mineral composition: Calcite/CaCO₃ or Silica/SiO₂)
sedimentary
Amber
Fossilized Tree Resin (Succinate)
mineral
Pearl
Aragonite (CaCO3) with Conchiolin
mineral
Aragonite Star Cluster
Aragonite (Calcium Carbonate, CaCO3)
mineral
Fossiliferous Limestone (with Crinoids/Coral)
Fossiliferous Limestone (CaCO3)
sedimentary
Calcite
Calcium Carbonate (CaCO3)
mineral
Fossilized Shark Teeth
Carcharhiniformes or Lamniformes species (common mineral: Fluorapatite/Ca5(PO4)3F)
sedimentary (fossilized organic matter)
Fossilized Bone (Petrified Bone)
Permineralized Vertebrate Remains
sedimentary
Horn Coral Fossil
Rugose coral (Order Rugosa)
fossil
Pearl
Calcium Carbonate (mostly Aragonite), CaCO3 (with conchiolin)
mineral
Pearl
Calcium Carbonate (primarily Aragonite and Calcite), CaCO3
mineral
Limestone with Fossil Inclusion
Calcium Carbonate (CaCO3) - Bioclastic Limestone
sedimentary
Mahogany Obsidian
Volcanic glass (SiO2 with Hematite or Magnetite inclusions)
igneous
Amber
Succinite (Fossilized Tree Resin)
mineraloid
Pyrite
Iron Disulfide (FeS2)
mineral
Pearl
Calcium Carbonate (CaCO3) with Conchiolin
mineral
Bivalve Fossil (Clam)
Class Bivalvia (e.g., Mercenaria or similar genus)
fossil