Fossilized tooth, likely mammalian molar
Indeterminate Mammalia; mineralized dentine and enamel
fossil
Category
Organic Gemstone (Not A Rock Or Mineral In The Traditional Sense, But Bio Mineralized Material)
Browse organic gemstone (not a rock or mineral in the traditional sense, but bio mineralized material) specimens identified by the Rock Identifier community.
Learn about Organic Gemstone (Not A Rock Or Mineral In The Traditional Sense, But Bio Mineralized Material) in the encyclopedia
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Shark Tooth Fossil
Vertebrate fossilized tooth (various genera such as Carcharodon, Otodus, or Negaprion)
fossil
Fossil Shell
Brachiopod or Mollusk fossil
fossil
Quartz-veined Limestone
Sedimentary limestone with quartz/calcite veinlets
sedimentary
Quartz
Silicon Dioxide (SiO2)
mineral
Sandstone
Sandstone (Siliciclastic Sedimentary Rock)
sedimentary
Chalcedony
Cryptocrystalline Quartz (SiO2)
mineral
Petrified Wood
Silicified Wood (SiO2)
fossil
Yellow Jasper
Silicon dioxide (SiO2) with iron oxide inclusions
mineral
Sandstone
Arenite (SiO2 composed primarily of quartz)
sedimentary
Chert
Silicon dioxide (SiO2)
Sedimentary
Fossilized Bone
Permineralized Vertebrate Bone
fossil
Poppy Jasper
Microcrystalline Quartz (SiO2) with mineral inclusions
sedimentary
Anthracite Coal
Anthracite (a variety of coal, predominantly carbon)
Sedimentary Rock (Metamorphosed)
Quartz-rich pegmatite or quartz vein rock
Mostly quartz (SiO₂), with probable feldspar and iron-oxide staining
igneous
Iron-rich breccia (likely hematite–goethite breccia)
Hematite (Fe₂O₃) and goethite (FeO(OH)) in a silicified or iron-cemented breccia
sedimentary
Petrified Wood
Silicified Wood (SiO2)
mineral
Chert (Gray Chalcedony)
Microcrystalline Quartz (SiO2)
sedimentary
Massive Quartz
Silicon Dioxide (SiO2)
mineral
Rounded iron-rich pebble
Likely hematite/goethite-bearing quartzite or ironstone; exact identification requires testing
mineral
Green Calcite
Calcite (CaCO3)
mineral
Tiger's Eye (Jasper-like Chalcedony)
Silicon dioxide (SiO2) - Pseudomorph after Crocidolite
metamorphic
Iron-stained quartz vein fragment
Quartz (SiO₂), likely with limonite/goethite iron oxides and minor sulfides
mineral
Amber / Copal
Succinite (fossilized tree resin)
mineraloid
![Turquoise (Hydrous phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]) — mineral](https://media.rockidentification.com/bacc5567-052c-4219-b556-3474bdf7571f-thumbnail.jpg)
Turquoise
Hydrous phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]
mineral
Sandstone
Arenite
sedimentary
Sandstone
Arenite
sedimentary
Amber
Succinite (fossilized tree resin)
fossil
Sandstone
Sandstone (SiO2-dominated clastic rock)
sedimentary
Sandstone with Iron Staining
Clastic sedimentary rock (primarily SiO2 with Fe2O3 staining)
sedimentary
Shark Tooth Fossil
Chondrichthyes (class) fossilized tooth
fossil
Pearl (as a biogenic mineral/gemstone)
Calcium Carbonate (mostly Aragonite), CaCO3
mineral
Red Jasper
SiO2 (Silicon Dioxide with Iron Oxide inclusions)
mineral
Fossil gastropod in granite-like stone
Gastropoda indet.; enclosing rock likely polished granite or gneiss
fossil
Fossilized Brachiopod
Brachiopoda (Phylum)
fossil
Moss agate bracelet
Chalcedony (microcrystalline quartz, SiO₂) with chlorite/amphibole inclusions
gemstone
Quartz-rich breccia or altered granite fragment
Polymineralic quartz–feldspar rock, likely hydrothermally altered granite/pegmatite
igneous
Amber
Fossilized Tree Resin (C10H16O)
mineral
Hessonite Garnet (Grossular)
Ca3Al2(SiO4)3 (Grossular Garnet)
gemstone
Sandstone
Sandstone (Quartz-rich Arenite / SiO2)
sedimentary
Blue Zircon
Zircon (Zirconium Silicate), ZrSiO4
gemstone
Sedimentary Sandstone
Arenite (Sedimentary Rock)
sedimentary