Ironstone Concretion
Siderite or Hematite Concretion
sedimentary
Category
Organic Mineral
Browse organic mineral specimens identified by the Rock Identifier community.
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Starfish Fossil
Asteroidea fossil
fossil
Fossil Shark Tooth
Chondrichthyes tooth fossil
fossil
Chert (Common Opal/Agatized Rock)
Microcrystalline Quartz (SiO2) with potential Chalcedony/Opaline silica
sedimentary
Chert (containing Iron Oxide)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Jasper/Mudstone)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (often called Jasper or Flint)
Microcrystalline Silica (SiO2)
sedimentary
Chert (with Limestone matrix)
Silicon dioxide (SiO2)
sedimentary
Chert (with Quartz vein/coating)
Microcrystalline Quartz (SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2 permineralization)
fossil
Pearl
Calcium Carbonate (Aragonite/Calcite) with Conchiolin
gemstone
Petrified Wood
Silicified Wood (SiO2)
fossil
Petrified Wood
Siliconized Wood (SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2 - Silicon Dioxide)
sedimentary
Chert (Jasper/Flint variant)
Silicon Dioxide (SiO2)
sedimentary
Chert (Jasper variation)
Silicon Dioxide (SiO2)
sedimentary
Chert (Flint)
Microcrystalline quartz (SiO2)
sedimentary
Amber
Succinite (specifically for Baltic amber); C10H16O (Variable organic compound)
mineral
Amber
Fossilized Tree Resin (C10H16O)
gemstone
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
fossil
Black Jasper
Black Jasper (Silicate mineral - SiO2)
sedimentary
Fossil gastropod shell
Fossilized marine gastropod; exact genus/species requires locality and examination
fossil
Amber (Rough)
Succinite (Resinite)
gemstone
Tufa (Limestone)
Calcareous Tufa (CaCO3)
sedimentary
Amber Inlay Jewelry
Fossilized Resin (C10H16O)
Organic Gemstone (Biogenic)
Shungite
Fullerene-bearing carbonaceous rock
mineral
Petrified Wood
Silicified Wood (SiO2)
mineral
Pearl
Aragonite / Calcium Carbonate (CaCO3)
mineral
Pyrite Geode (Sparkling Druzy)
Iron Sulfide (FeS2) in Sedimentary Nodule
mineral
Pearl
Biogenic Calcium Carbonate (Aragonite/Calcite), CaCO3
mineral
Chert (Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Dinosaur Fossil Tooth
Vertebrate Fossilized Tooth
fossil
Fossil Shark Tooth
Selachii (fossilized dentition)
fossil
Bivalve Fossil (Fossilized Shell)
Class Bivalvia (fossilized in Calcium Carbonate/Aragonite)
fossil
Fossil Coral
Scleractinia or Anthozoa (Fossilized)
fossil
Petrified Wood
Silicified Wood (primarily SiO2)
fossil
Chert (often called Jasper in this color variety)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Flint/Chalcedony)
Microcrystalline Quartz (SiO2)
sedimentary
Fossilized Tiger Shark Tooth
Galeocerdo cuvier (fossilized hydroxylapatite)
sedimentary
Chert (specifically Flint or Jasper variant)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary