Spiny Oyster Shell
Spondylus (Calcium Carbonate, CaCO3)
mineral
Category
Mineral And Organic Gemstone
Browse mineral and organic gemstone specimens identified by the Rock Identifier community.
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Morganite and Aquamarine (Beryl) Bracelet
Beryllium aluminum silicate, Be3Al2(SiO3)6
gemstone
Eclogite (retrograded)
Eclogite (Omphacite-Garnet rock)
metamorphic
Corundum (Ruby Variety)
Corundum (Al2O3)
mineral
Diamond (Colorless/White)
Carbon (C)
mineral
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Chert (and Chert-based Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Sedimentary
Chert (and Quartzite)
Microcrystalline silica (SiO2)
sedimentary
Mother of Pearl (Nacre)
Calcium Carbonate (primarily aragonite, with conchiolin)
Organic Gemstone/Biomineral
Petrified Wood
Silicified wood (Quartz, Chalcedony, or Opal)
sedimentary
Fossil Shark Tooth
Odontaspididae (likely Carcharias sp.)
fossil
Petrified Bone Pebble
Silicified Fossilized Bone
fossil
Fossilized Crab Carapace (Concretion)
Decapoda (fossil), typically preserved in calcite or siderite concretion
sedimentary
Chert (Nodule)
Silicon Dioxide (SiO2)
sedimentary
Moqui Marbles
Iron Oxide Concretion (Hematite/Goethite)
sedimentary
Petrified Wood
Silicified wood (primarily SiO2)
sedimentary
Petrified Wood
Silicified wood (primarily SiO2)
metamorphic
Fossilized Oyster Shell (Limestone/Coquina)
Crassostrea (Fossilized Bivalve), Calcium Carbonate (CaCO3)
sedimentary
Fossil Shark Tooth
Carcharadon sp. (likely Carcharodon carcharias or similar Lamniformes)
fossil
Green Sandstone
Glauconitic Sandstone
sedimentary
Moss Agate
Silicon dioxide (SiO2) with inclusions
Mineral
Botryoidal Hemimorphite
Hemimorphite (Zn4Si2O7(OH)2·H2O)
mineral
Chert / Flint
Microcrystalline or cryptocrystalline quartz (SiO2)
sedimentary
Baroque Pearl
Biogenic Calcium Carbonate (Aragonite/Conchiolin)
mineral
Amber
Succinite (specifically for Baltic amber); C10H16O (Variable organic compound)
mineral
Chert (Chalcedony)
Silicon Dioxide (SiO2)
sedimentary
Tufa (Limestone)
Calcareous Tufa (CaCO3)
sedimentary
Petrified Wood
Silicified wood (Quartz, SiO2)
metamorphic
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Dendritic Agate / Moss Agate
Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions
mineral
Moss Agate
Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite
mineral
Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with dendritic inclusions
mineral
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Amber
Fossilized Tree Resin (Amorphous Hydrocarbon)
Mineral
Chert (varietal Flint or Jasper)
Microcrystalline Quartz (SiO2)
sedimentary
Granite
Phaneritic Igneous Rock (Granite)
igneous
Olivine (Peridotite)
Magnesium iron silicate (Mg, Fe)2SiO4
igneous
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
Chert / Flint
Microcrystalline or cryptocrystalline quartz (SiO2)
sedimentary