Graphite
Graphite (C)
mineral
Category
Organic (Sedimentary Context)
Browse organic (sedimentary context) specimens identified by the Rock Identifier community.
Learn about Organic (Sedimentary Context) in the encyclopedia
View all →
Petrified Wood
Silicified Wood (primarily SiO₂ / Silicon Dioxide)
mineral
Arid Sandy Loam
Arenosols / Regosols
sedimentary
Coal (specifically Bituminous or Anthracite)
Organic sedimentary rock; primarily Carbon (C) with varying H, S, O, N
sedimentary
Amber Inlay Jewelry
Fossilized Resin (C10H16O)
Organic Gemstone (Biogenic)
Fossiliferous Limestone
Calcium Carbonate (CaCO3) with Bioclasts
sedimentary
Amber
Succinite (fossilized tree resin, C10H16O)
fossil
Seashell Fossil
Invertebrate fossil (phylum Mollusca)
fossil
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Banded Sedimentary Rock (Siltstone/Mudstone with concretion)
Siltstone with Ferruginous Banding
sedimentary
Chert (Smooth River Pebble)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Jasper with Quartz Vein
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Yellow Jasper (Iron-stained Chert)
Silicon Dioxide (SiO2) with iron oxide (Limonite/Goethite) inclusions
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Fossil Coral (Favosites Honeycomb)
Favosites (Genus), Phylum Cnidaria, Class Anthozoa
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Jasper (Iron-stained Chert)
Silicon Dioxide (SiO2) with impurities of Hematite or Goethite
sedimentary
Fossilized Brachiopod
Brachiopoda (e.g., Atrypa or Rhynchonellida)
fossil
Petoskey Stone
Hexagonaria percarinata (Fossilized Rugose Coral)
sedimentary
Fossilized Sand Tiger Shark Tooth
Carcharias taurus / Striatolamia macrota (mineralized as Hydroxylapatite/Francolite)
sedimentary (fossil)
Petrified Wood
Silicon Dioxide Fossilized Wood (SiO2)
fossil
Petrified Wood with Lichen
Silicified Wood (SiO2) colonized by crustose lichens
fossil
Chert / Flint
Chert (varieties include Flint)
Sedimentary
Asphalt (Bituminous pavement)
Bituminous concrete / Asphalt
Sedimentary (Anthropogenic)
Jasper (Petrified Wood variant)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Grey and White Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Stromatolite (Jasper-replaced)
Fossilized Stromatolite (Cyanobacteria / Cryptozon / Silica SiO2)
sedimentary
Chert (Flint Pebbles)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (specifically Tan/Yellow Chert)
Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)
sedimentary
Amber
Succinite (with formula approximately C10H16O)
Organic mineraloid
Fossil Coral
Phylum Cnidaria / Rugosa or Tabulata
fossil
Petrified Wood
Silicified Wood (Quartzo-feldspathic fossil wood)
fossil
Petrified Wood
Silicified wood (Quartz, SiO2)
metamorphic
Gneiss
Gneiss (pronounced 'nice')
Metamorphic Rock
Petrified Wood
Silicified Wood (SiO2)
metamorphic
Shark Tooth Fossil
Vertebrate fossilized tooth (various genera such as Carcharodon, Otodus, or Negaprion)
fossil
Amber (specifically Cherry Amber)
Succinite (with the chemical formula C10H16O)
Organic Gemstone (not a mineral)
Septarian Nodule
Septarian Concretion (CaCO3 with Siderite/Calcite/Aragonite)
sedimentary
Chert (Hag Stone / Hole Stone)
Chert (Cryptocrystalline variety of Quartz, SiO2)
sedimentary
Glauconitic Sandstone (or Greensand)
Glauconitic Siliciclastic Rock (Containing (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)
sedimentary
Banded Chert (Jasper)
Silicon Dioxide (SiO2)
sedimentary
Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary