Tree Agate (also known as Dendritic Agate)
Silicon Dioxide with inclusions (SiO2 + Mn/Fe)
Category
Browse organic gemstone specimens identified by the Rock Identifier community.
Tree Agate (also known as Dendritic Agate)
Silicon Dioxide with inclusions (SiO2 + Mn/Fe)
Banded Chert
Sedimentary Cryptocrystalline Quartz (SiO2)
Ferruginous Sandstone with Concretion
Sandstone (SiO2 dominated with Fe2O3 cement)
Travertine
Terrestrial Sedimentary Limestone (CaCO3)
Stromatolite
Biogenic Sedimentary Rock (composed predominantly of CaCO3)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert
Chert (Microcrystalline Quartz, SiO2)
Banded Chert
Silicon Dioxide (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Fossiliferous Limestone
Limestone with embedded fossil cross-section
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
Chert / Flint
Chert (SiO2)
Chert (Arrowhead Preform or Point)
Chert (Microcrystalline Quartz, SiO2)
Chert (Flint)
Cryptocrystalline Quartz (SiO2)
Chert (Flint)
Chert (SiO2)
Chert (Jasper)
Microcrystalline Quartz (SiO2)
Shungite
Non-crystalline carbon (allotrope of carbon)
Chert (Flint)
Silicon dioxide (SiO2)
Glauconite (Greensand)
(K, Na)(Fe3⁰, Al, Mg)₂(Si, Al)₄O₁₀(OH)₂
Quartz River Pebble with Algae
Silicon Dioxide (SiO2) with organic biofilm
Amber (with potentially inclusions)
Succinite (Fossilized Tree Resin)
Dendritic Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with inclusions
Baroque Pearl
Biogenic Calcium Carbonate (Aragonite/Conchiolin)
Petrified Wood
Silicified Wood (SiO2)
Pyritized Ammonite
Ammonitida (replaced by Iron Disulfide, FeS2)
Fossilized Chiton (Polyplacophora)
Polyplacophora (fossilized valves)
Nacre (Mother of Pearl)
Nacre (Biogenic Aragonite/Calcite composite, CaCO3)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert (Jasper)
Silicon dioxide (SiO2)
Chert (Jasper variety)
Microcrystalline Quartz (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Shungite
Non-crystalline carbon (Fullerenes)
Amber
Succinite (Resin C10H16O)
Zebra Rock / Zebra Marble
Banded Limestone-Marble Transition
Amber
Succinite (Fossilized Tree Resin)
Amber
Succinite (fossilized resin)
Amber
Succinite (fossilized tree resin)
Amber
Succinite
Amber
Succinite (Formula: C10H16O)
Black Limestone with Calcite Veins
Limestone (Calcium Carbonate, CaCO3)
Fossil Crab
Decapoda (likely Avitelmessus or Raninidae family)