Banded Chert
Microcrystalline Quartz (SiO2)
sedimentary
Category
Mineral And Organic Gemstone
Browse mineral and organic gemstone specimens identified by the Rock Identifier community.
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Oyster Shell Fragment
Crassostrea virginica (or related Bivalvia)
fossil
Sandstone
Arenite
sedimentary
Petrified Wood
Silicified Wood (SiO2)
fossil
Rough Garnet (Almandine)
Almandine Garnet (Fe3Al2(SiO4)3)
mineral
Fossilized Bone
Petrified Bone (Fluorapatite / Calcium Phosphate replacement)
fossil
Chert (includes Flint & Jasper)
Chert (Siliceous sedimentary rock, chemical formula SiO2)
sedimentary
Quartz-rich crystal cluster (likely milky quartz)
Quartz, silicon dioxide (SiO₂)
mineral
Milky quartz (iron-stained quartz)
Quartz, silicon dioxide (SiO₂)
mineral
Clear quartz crystal fragment
Quartz, silicon dioxide (SiO₂)
mineral
Clear quartz sphere
Quartz (silicon dioxide, SiO₂), likely rock crystal or low-grade milky quartz
mineral
Quartz Geode
Crystalline Silicon Dioxide (SiO2) in sedimentary/volcanic host
mineral
Unidentified polished dark stone with a possible quartz fragment
Indeterminate; appearance may reflect polished basalt, obsidian, or iron-rich rock, with a pale quartz/feldspar inclusion
mineral
Fossilized Bivalve Shell
Class Bivalvia (fossilized)
fossil
Enrolled Trilobite Fossil
Phylum Arthropoda, Class Trilobita (likely Calymene or Flexicalymene)
fossil
Shark Tooth Fossil
Chondrichthyes (class) fossilized tooth
fossil
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (varieties include Flint and Jasper)
Silicon Dioxide (SiO2)
sedimentary
Banded Calcite (Zebra Calcite)
Calcite (CaCO3) with trace organic or oxide inclusions
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Chalcedony (Chert/Flint)
Silicon Dioxide (SiO2)
sedimentary
Jasper
Silicon dioxide (SiO2) with impurities
sedimentary
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
mineral
Fossilized Bone
Permineralized Vertebrate Bone
fossil
Amber / Copal
Organic resin, C10H16O
mineral
Moss Agate
Silicon Dioxide (SiO2) with inclusions of manganese or iron oxide
mineral
Petrified Wood
Silicified Wood (SiO2 - Quartz/Chalcendony replacing organic matter)
sedimentary
Chert (specifically Flint or Common Chert)
Microcrystalline Quartz (SiO2)
sedimentary
Amber / Copal
Fossilized Tree Resin (Succinate)
Mineraloid
Petrified Wood
Silicified Wood (SiO2)
fossil
Moss Agate
Silicon Dioxide (SiO2) with inclusions of manganese or iron oxides
mineral
Garnet (Almandine-Pyrope)
Almandine-Pyrope Mg3Al2(SiO4)3 to Fe3Al2(SiO4)3
mineral
Fossilized Shark Tooth
Chondrichthyes (Class)
fossil
Chert (Nodular or Massive Variety)
Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Sunstone
Oligoclase (Plagioclase Feldspar) with hematite or copper inclusions
mineral
Coral (Precious Coral)
Corallium rubrum (Red Coral), Paracorallium japonicum (Momo Coral), Pleurocorallium elatius (Sardinian Coral), various other species within the Corallidae family. Chemically, it's primarily Calcium Carbonate (CaCO 3 ).
Mineral, Organic Gemstone
Chert / Flint
Silicon Dioxide (SiO₂)
sedimentary
Ironstone Concretion
Siderite or Limonite Concretion (FeCO3 or FeO(OH)·nH2O)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
fossil
Chert (Jasper-rich)
Silicon Dioxide (SiO2)
sedimentary
Fossil Shark Tooth
Chondrichthyes (class); likely Lamniformes (order) fossilized in Apatite/Hydroxyapatite
fossil