Ambergris
Ambra grisea (Metabolic byproduct)
Category
Browse organic (geological relative) specimens identified by the Rock Identifier community.
Ambergris
Ambra grisea (Metabolic byproduct)
Chalcopyrite
CuFeS2
Fossiliferous Brachiopod in Shale
Brachiopoda (Phylum) preserved in Carbonaceous Shale
Ironstone Concretion / Limonite Node
Goethite and Limonite (FeO(OH) nH2O)
Ironstone Concretion (Boxwork)
Siderite-Limonite Concretion (FeO(OH)·nH2O)
Pearl
Calcium Carbonate (Aragonite/Calcite) with Conchiolin
Limestone
Sedimentary Calcium Carbonate (CaCO3)
Limestone
Calcium Carbonate (CaCO3)
Ironstone Concretion
Goethite-rich Siltstone / Siderite (FeCO3)
Ironstone Concretion
Siderite or Goethite Concretion
Fossiliferous Limestone
Bioclastic Limestone (CaCO3)
Anthracite Coal
Anthracite (Metamorphic/High-grade Sedimentary Coal)
Sandstone
Sedimentary Rock (Quartz arenite/Arkose)
Shungite
Shungite (Non-crystalline carbon, C)
Ironstone Concretion (Limonite/Goethite)
Goethite/Limonite concretion (FeO(OH)·nH2O)
Limestone (River or Sea Cobble)
Calcium Carbonate (CaCO3)
Limestone (River Pebble)
Calcium Carbonate (CaCO3)
Chert Nodules or Concretion
Cryptocrystalline Quartz (SiO2)
Travertine
Terrestrial Sedimentary Limestone (CaCO3)
Banded Chert
Microcrystalline Quartz (SiO2)
Ironstone Concretion (Limonite/Goethite)
Iron oxide concretion (contains FeO(OH)·nH2O)
Ironstone Concretion
Siderite or Limonite Concretion (FeCO3 or FeO(OH)·nH2O)
Pink Opal
Hydrated silica (SiO2 "n H2O)
Amber
Succinite
Amber
Succinite (Fossilized Resin)
Fossilized Shark Tooth
Scapanorhynchus (Sand Tiger Shark relative)
Amber
Succinite (fossilized resin)
Black Dolomite
Bituminous Dolomite (CaMg(CO3)2)
Pyrite with Vesicular Matrix
Iron Disulfide (FeS2)
Ironstone Concretion
Ironstone (Limonite/Goethite Concretion)
Rough Amber (likely Copal or immature Amber)
Organic gemstone / Succinite (if Baltic)
Fossil Shell Fragment (possibly Brachiopod or Bivalve)
Calcium Carbonate (CaCO3) - Phylum Brachiopoda or Mollusca
Ironstone / Hematite
Iron(III) oxide (Fe2O3)
Picasso Jasper (or Picasso Marble)
Metamorphosed Limestone (Calcium Carbonate, CaCO3, with impurities)
Kidney Stone
Nephrolithiasis (Calcium Oxalate, Hydroxyapatite, or Uric Acid)
Banded Sedimentary Rock
Sedimentary rock with Liesegang banding
Sandstone Geode
Sedimentary Geode (Silica/Calcite composition)
Quartz Vein in Amphibolite / Gneiss
Quartz (SiO2) in Mafic Metamorphic Host Rock
Argillite
Argillite (compact, clay-rich sedimentary rock)
Likely lateritic ironstone (limonite/goethite-rich)
Goethite, α-FeO(OH), with possible limonite and clay impurities
Banded Chert
Silicon Dioxide (SiO2)
Sandstone
Clastic sedimentary rock (primarily quartz arenite)