Pearl
Calcium Carbonate (Aragonite) with Conchiolin; formula: CaCO3
mineral
Category
Organic Gemstone (Fossilized Resin)
Browse organic gemstone (fossilized resin) specimens identified by the Rock Identifier community.
Petoskey Stone
Hexagonaria percarinata (Fossilized Rugose Coral)
sedimentary
Petoskey Stone
Hexagonaria percarinata
sedimentary
Precious Red Coral
Corallium rubrum (Calcium Carbonate, CaCO3)
Mineral (Organic Gemstone)
Devil's Toenail
Gryphaea (extinct genus of foam oysters, typically composed of Calcite CaCO3)
sedimentary
Engineer Quartz/Quartzite
SiO2 (Silicon Dioxide with binders)
Sedimentary or metamorphic-derived
Engineered Quartz Stone
Agglomerated Quartz (SiO2 + Polymer Resin)
mineral-based composite
Acrylic or Resin (Synthetic Imitation)
Polymethyl Methacrylate (PMMA) or Polyepoxide
Synthetic/Man-made Polymer
Sandstone
Arenite (SiO2 primarily)
sedimentary
Petoskey Stone (Coral Fossil)
Hexagonaria percarinata (Fossilized colonial rugose coral)
sedimentary
Dendritic Agate (River Pebble)
Silicon Dioxide (SiO2) with Manganese or Iron oxide inclusions
mineral
Picture Jasper
Jasper (Silicon Dioxide, SiO2 with impurities)
sedimentary
Sandstone
Arenite (composed primarily of SiO2)
sedimentary
Dendritic Quartz
Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions
mineral
Fossilized Horn Coral
Rugosa
fossil
Mookaite Jasper
Silicified Radiolarite (SiO2)
sedimentary
Blue Chalcedony
Silicon Dioxide (SiO2) - Microcrystalline Quartz
mineral
Devil's Toenail (Fossil Oyster)
Gryphaea arcuata (Calcium Carbonate, CaCO3)
sedimentary
Kambaba Jasper
Stromatolite (Microbial mat fossil in silicified sediment)
sedimentary
Sandstone
Arenite
sedimentary
Sandstone (Ferruginous)
Clastic Sedimentary Rock (SiO2 with Fe2O3/FeOOH cement)
sedimentary
Moss Agate
Chalcedony (SiO2) with inclusions of manganese or iron oxide
mineral
Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Shale
Shale (clastic sedimentary rock)
Sedimentary
Sandstone (Quartz Arenite)
Sandstone (SiO2 with possible mineral cements)
sedimentary
Petoskey Stone
Hexagonaria percarinata (Fossilized Rugose Coral)
sedimentary
Shungite
Non-crystalline carbonoid (Shungite)
metamorphic
Kambaba Jasper
Stromatolite (Fossilized Algae within Microcrystalline Quartz)
sedimentary
Chakra Stone Tower (Composite Multi-Mineral)
Crystalline Silicon Dioxide composite (SiO2) with various inclusions
mineral
Conglomerate
Conglomerate (clastic sedimentary rock)
sedimentary
Sandstone (Ferruginous)
Arenite (Fe-rich)
sedimentary
Dendritic Jasper (River Stone)
Silicon Dioxide (SiO2) with Manganese/Iron Oxide inclusions
sedimentary
Petoskey Stone (Fossilized Rugose Coral)
Hexagonaria percarinata (Calcium Carbonate, CaCO3)
sedimentary
Precious Coral
Corallium rubrum (Calcium carbonate with trace carotene)
Organic gemstone / Sedimentary mineraloid
Petrified Wood
Silicified wood (primarily Silicon Dioxide, SiO2)
sedimentary
Fossil Coral (likely Favosites or Honeycomb Coral)
Class Anthozoa, Order Tabulata, Genus Favosites
sedimentary
Chert (containing a small fossil)
Microcrystalline Quartz (SiO2)
sedimentary
Petoskey Stone
Hexagonaria percarinata (Fossilized Rugose Coral)
sedimentary
Petoskey Stone
Hexagonaria percarinata (Fossilized Rugose Coral)
sedimentary
Megalodon Shark Tooth Fossil
Otodus megalodon (fossilized in sedimentary matrix)
sedimentary
Fossilized Coral (Petoskey-style)
Hexagonaria percarinata (Fossilized Rugose Coral)
sedimentary
Rugose Coral (Horn Coral Fossil)
Order Rugosa (fossilized in limestone/chert)
sedimentary