Petrified Wood
Silicified Wood (SiO2)
mineral
Category
Organic Materia (Not A Rock Or Mineral)
Browse organic materia (not a rock or mineral) specimens identified by the Rock Identifier community.
Learn about Organic Materia (Not A Rock Or Mineral) in the encyclopedia
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Shungite
Shungite (Non-crystalline carbon, C)
mineral
Geode
Quartz nodule / Chalcedony-lined cavity
sedimentary
Mixed Rock and Mineral Collection
Various geological specimens
igneous, sedimentary, and metamorphic
Banded Chert
Microcrystalline Quartz (SiO2)
sedimentary
Oyster Shell Fragment
Crassostrea virginica (or related Bivalvia)
fossil
Amber
Succinates (fossilized tree resin), approximately C10H16O
organic gemstone
Petrified Wood
Silicified Wood (SiO2)
fossil
Sandstone Pebble with Mineral Encrustation
Quartz Sandstone with Calcite/Halite Crust
sedimentary
Crushed Granite and Basalt
Phaneritic Igneous Rock / Aphanitic Igneous Rock
igneous
Amber
Fossilized Tree Resin (C10H16O)
gemstone
Glauconitic Sandstone
Glauconitic Quartz Arenite
sedimentary
Druzy Quartz on Limestone
Silicon Dioxide (SiO2) on Calcium Carbonate (CaCO3)
sedimentary
Banded Chert
Chert (a microcrystalline variety of quartz, SiO2 with minor impurities)
Sedimentary
Chert (Flint with Iron Staining)
Silicon Dioxide (SiO2)
sedimentary
Chert (Flint)
Silicon Dioxide (SiO2)
sedimentary
Tumbled brown quartz/chert pebble
Microcrystalline quartz (SiO₂), possibly chert or jasper
mineral
Moss Agate
Silicon Dioxide (SiO2) with inclusions
mineral
Moss Agate
Chalcedony (SiO2) with inclusions of manganese or iron oxides
mineral
Tiger Shark Fossil Tooth
Galeocerdo cuvier (fossilized)
sedimentary
Green Fluorite
Fluorite (Calcium Fluoride, CaF2)
mineral
Amber
Succinite (C10H16O)
mineral
Black Pearl (Tahitian-style Cultured Pearl)
Calcium Carbonate (Aragonite) with Conchiolin (CaCO3)
mineral
Moss Agate
Cryptocrystalline Quartz (SiO2 with manganese or iron oxide inclusions)
mineral
Pyrite
Iron Disulfide (FeS2)
mineral
Fossiliferous Limestone
Calcium Carbonate (CaCO3)
sedimentary
Fossil Coral / Crinoid Stem section
Anthozoa / Crinoidea fossil
fossil
Precious Coral
Corallium rubrum (Calcium carbonate with trace carotene)
Organic gemstone / Sedimentary mineraloid
Moss Agate
Silicon Dioxide (Chalcedony with green mineral inclusions), SiO2
gemstone
Ironstone Concretion
Siderite or Limonite Concretion (FeCO3 or FeO(OH)·nH2O)
sedimentary
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
sedimentary
Petrified Wood
Silicified wood (primarily Silicon Dioxide, SiO2)
sedimentary
Shark Tooth Fossil
Otodus obliquus (or similar prehistoric lamniform shark tooth)
fossil
Wood Jasper
Siliceous sedimentary rock (variety of Chert/Chalcedony)
Sedimentary
Chert (Nodule)
Cryptocrystalline Quartz (SiO2)
sedimentary
Vein Quartz in Basalt or Mafic Rock
Silicon Dioxide (Quartz veins in volcanic host rock)
igneous
Pyrite (Pseudomorph)
Iron Sulfide (FeS2)
mineral
Sandstone (with Iron Staining)
Arenite (primarily SiO2 with Fe2O3/FeO(OH) oxides)
sedimentary
Chert (specifically Flint or Jasper variant)
Microcrystalline Quartz (SiO2)
sedimentary
Quartz Vein in Basalt or Mafic Rock
Silicon Dioxide (SiO2) vein in volcanic/mafic matrix
igneous
Petrified Wood
Silicified wood (primarily SiO2)
fossil
Dendritic Agate
Silicon Dioxide with inclusions (SiO2 + Mn/Fe)
mineral