Pyrite
Iron Disulfide (FeS2)
mineral
Category
Organic (Biological Specimen)
Browse organic (biological specimen) specimens identified by the Rock Identifier community.
Pearl necklace
Pearl (biogenic calcium carbonate, chiefly aragonite; CaCO₃)
gemstone
Sandstone (Weathered Cobble)
Clastic sedimentary rock (primarily SiO2)
sedimentary
Fossilized oyster or other bivalve shell
Calcitic bioclast, commonly Ostrea spp. or Exogyra spp.
fossil
Chert / Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Amber
Succinite
Organic (Mineraloid)
Pyrite
Iron Sulfide (FeS2)
mineral
Shark Tooth Fossil
Vertebrate fossilized tooth (various genera such as Carcharodon, Otodus, or Negaprion)
fossil
Amber
Succinite (with formula approximately C10H16O)
Organic mineraloid
Amber
Succinicum (Succinite); C10H16O
Mineraloid (Organic)
Pyrite
Iron Sulfide (FeS2)
mineral
Fossilized Shark Tooth
Chondrichthyes (Class)
fossil
Chert (Jasper/Chalcedony mix)
Microcrystalline Quartz (SiO2)
sedimentary
Sandstone with Foliose Lichen
Arenite (Rock matrix) with Xanthoparmelia or Flavoparmelia (Lichen genus)
sedimentary
Fossiliferous limestone, possibly containing a brachiopod or bivalve fossil
Calcite-rich limestone (CaCO₃), with an apparent shell impression or shell fragment
fossil
Dinosaur Bone (Petrified/Agatized)
Permineralized Dinosauria Bone (Silicate Replacement)
fossil
Calcite
Calcium Carbonate (CaCO3)
mineral
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Amber
Succinite (fossilized tree resin)
mineraloid / sedimentary organic material
Chert
Microcrystalline Quartz (SiO2)
sedimentary
Vesicular Basalt (Scoria)
Basalt with vesicular texture
igneous
Calcite
Calcium Carbonate (CaCO3)
mineral
Weathered limestone pebble
Limestone, primarily calcite (CaCO₃)
sedimentary
Chert / Chalcedony Nodule
Silicon Dioxide (SiO2)
sedimentary
Likely limestone or calcareous fossil fragment
Calcite-rich carbonate rock; possibly bioclastic limestone (CaCO₃)
sedimentary
Kidney Stone
Calcium Oxalate (CaC2O4·nH2O)
mineral
Chert (containing fossil leaf impression)
Microcrystalline silicon dioxide (SiO2)
sedimentary
Firewood (Wood Log)
Lignum (Plant tissue composed of cellulose and lignin)
Organic (Non-geological)
Chert (Green Fossilized Algae or Jasper)
Silicon Dioxide (SiO2)
sedimentary
Limestone with Chert Nodule
Carbonate rock (CaCO3) with Microcrystalline Silicon Dioxide (SiO2) inclusion
sedimentary
Fossiliferous Shale
Carbonaceous Shale (with potential plant/aquatic fossils)
sedimentary
Amber
Succinite (C10H16O)
Organic Mineraloid
Fossilized Shark Tooth
Carcharocles sp. or similar (Fossilized Fluorapatite)
sedimentary
Amber
Succinite (specifically for Baltic amber; general formula C10H16O)
Mineraloid (Organic)
Chert (River Pebble)
Microcrystalline Quartz (SiO2)
sedimentary
Paper (Cellulose)
Cellulose (C6H10O5)n
Organic (Anthropogenic)
Ambergris
Ambrein (C30H52O)
mineraloid / organic geological substance
Chert (Flint/Jasper)
Microcrystalline Quartz (SiO2)
sedimentary
Weathered limestone slab
Micritic limestone, primarily calcite (CaCO₃)
sedimentary
Agatized fossil fragment, possibly silicified coral
Chalcedony (microcrystalline SiO₂) replacing carbonate fossil material
fossil
Orange Calcite (likely polished specimen)
Calcite
Mineral
Marine invertebrate fossils (Brachiopods and Gastropods)
Phylum Brachiopoda and Class Gastropoda
fossil