Precious Coral
Corallium rubrum (Calcium carbonate with trace carotene)
Category
Browse sedimentary (fossilized organic remain) specimens identified by the Rock Identifier community.
Precious Coral
Corallium rubrum (Calcium carbonate with trace carotene)
Septarian Nodule (Dragon Stone)
Septarian Nodule (Calcium Carbonate/Aragonite/Calcite Concretion)
Anthracite Coal
Anthracite (Carbon-based organic sedimentary rock transitioned to metamorphic)
Shale or Argillite
Shale (sedimentary) / Argillite (metamorphic)
Kidney Stone
Calcium Oxalate (CaC2O4), Uric Acid, or Struvite
Pyrite
Pyrite (Iron Disulfide), FeS2
Graphite
Graphite (C)
Chert / Flint
Chert (varieties include Flint)
Banded Chert
Chert (a microcrystalline variety of quartz, SiO2 with minor impurities)
Coal (specifically Bituminous or Anthracite)
Organic sedimentary rock; primarily Carbon (C) with varying H, S, O, N
Tiger's Eye
Silicon dioxide (SiO2) with fibrous inclusions of crocidolite (riebeckite)
Druzy Chalcedony/Quartz on Fluorite core
Silicon Dioxide (SiO2) on Calcium Fluoride (CaF2)
Red Coral
Corallium rubrum (Calcium Carbonate, CaCO3 with Carotenoid pigments)
Pearl
Calcium Carbonate (CaCO3) + Conchiolin
Porphyritic Basalt or Diabase with Plagioclase Phenocrysts
Porphyritic Basalt or Diabase; Mineral: Plagioclase Feldspar
Shale or Argillite
Shale (fine-grained clastic sedimentary rock) or Argillite (low-grade metamorphic rock derived from shale)
Graphite-veined Quartzite
Meta-sedimentary Quartzite with Carbonaceous/Graphitic Inclusions (SiO2 + C)
Precious Coral (Red Coral)
Corallium rubrum (Calcium Carbonate, CaCO3)
Petrified Wood
Silicified Wood (primarily SiO₂ - Silicon Dioxide)
Pearl (incorporated into jewelry)
Aragonite and Calcite (CaCO3)
Chert (varietal: Jasper or Flint likely, but definitive identification is difficult from image)
SiO₂ (silicon dioxide)
Graphite
Graphite (Carbon, C)
Pink Opal / Peruvian Opal
Hydrated amorphous silicon dioxide (SiO2·nH2O)
Grass (Organic Matter/Soil)
Poaceae (family of monocotyledonous flowering plants)
Potassium-Rich Silicate Clay (inferred from biological context)
Phyllosilicate group (likely Illite or Smectite within surrounding soil substrate)
Precious Red Coral
Corallium rubrum (Calcium Carbonate, CaCO3)
Pink Coral
Corallium rubrum (Calcium Carbonate, CaCO3)
Paper (Cellulose)
Cellulose (C6H10O5)n
Turquoise and Red Coral
CuAl6(PO4)4(OH)8·4H2O (Turquoise) and Corallium rubrum (Red Coral)
Red Jasper (beads)
SiO₂ (Silicon Dioxide)
Pearl
Calcium carbonate (CaCO3) in the form of Aragonite or Calcite
Pearl
Calcium Carbonate (CaCO3) - Aragonite/Calcite
Turquoise and Red Coral (with Grizzly Bear Claw)
Turquoise (CuAl6(PO4)4(OH)8·4H2O) and Precious Coral (Corallium rubrum)
Pyrite
Pyrite (FeS2)
Oak-grain Laminate (Industrial/Decorative Furniture Finish)
Melamine Resin-impregnated Decorative Paper on Particleboard (Cellulose/Thermosetting Plastic)
Moss Agate
Chalcedony (SiO2) with inclusions of manganese or iron oxides
Stardust (Micrometeorite)
Chondrite / Micrometeorite (Extraterrestrial Silicate)
Moss Agate
Chalcedony (SiO2) with inclusions of hornblende or chlorite
Red Coral
Corallium rubrum
Onyx (Black) and Mother of Pearl Inlay
Silicon Dioxide (SiO2) for Onyx; Aragonite (CaCO3) for Mother of Pearl
Pearl and Garnet Glass
Calcium Carbonate (CaCO3) for pearl; Silicon Dioxide (SiO2) for glass
Natural Pearl (appearing in a jewelry setting)
Calcium Carbonate (mostly Aragonite), CaCO3 with Conchiolin