Chalk
Calcium Carbonate (CaCO3)
sedimentary
Category
Sedimentary (Fossil)
Browse sedimentary (fossil) specimens identified by the Rock Identifier community.
Chert (Iron-stained)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Dolomite or Limestone (Carbonate Rock)
CaMg(CO3)2 (Dolomite) or CaCO3 (Limestone / Calcite)
sedimentary
Sandstone or Mudstone with Iron Staining
Ferruginous Sandstone/Mudstone
Sedimentary
Sandstone
Sandstone (lithified arenite/wacke)
Sedimentary Rock
Chert (White Chert/Flint)
Chert (Microcrystalline or Cryptocrystalline Quartz, SiO2)
sedimentary
Anthracite Coal
Anthracite (Carbon-based solid)
metamorphic
Petrified Wood
Silicified Wood (primarily SiO₂ - Silicon Dioxide)
metamorphic
Amber
Succinite (fossilized tree resin), C10H16O
Organic Gemstone
Petrified Wood (Agatized/Silicified Wood)
Silicified Wood (SiO2)
metamorphic
Petrified Wood
Silicified Wood (SiO2)
Mineral / Fossil
Amber
Succinite (fossilized resin)
mineral
Amber
Resinite / Fossilized Tree Resin
mineral
Amber
Succinite (fossilized resin); C10H16O
mineraloid
Petoskey Stone
Hexagonaria percarinata (Fossilized Coral)
sedimentary
Crushed Stone (Gravel/Aggregates)
Crushed rock aggregate (varied composition including Granite, Limestone, and Quartz)
sedimentary and igneous (mixed)
Amber
Succinite (specific to Baltic amber), fossilized tree resin
mineraloid
Slate
Slate (Metamorphic Rock)
metamorphic
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Amber
Succinite (fossilized resin)
mineral
Amber
Succinite (Approximate formula: C10H16O)
mineral
Amber
Succinite (Approximate formula: C10H16O)
Mineraloid
Petrified Wood
Silicified Wood (SiO2 permineralization)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
mineral
Fighting Conch (Sea Shell)
Strombus alatus (primarily composed of Calcium Carbonate / CaCO3)
mineral
Asphalt (Bituminous Pavement Bit)
Bitumen-bound aggregate (Petrochemical-bound composite)
sedimentary (anthropogenic/technogenic)
Pyrite Sun (Pyrite Dollar)
Iron Disulfide (FeS2)
mineral
Fossilized Shark Tooth
Carcharodon (Galeocerdo sp. or Lamniform)
mineral
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Chert (within Asphalt)
Chert (SiO2)
sedimentary
Petrified Wood
Silicified wood (primarily Silicon Dioxide - SiO2)
metamorphic
Petrified Wood
Silicified Wood (SiO2 - Silicon Dioxide)
mineral
Amber
Succinite
Organic Mineral
Moss Agate / Carnelian Agate
Silicon Dioxide (SiO2) with iron and manganese inclusions
mineral
Dendritic Quartz Pebble
Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions
mineral
Desert Rose (Baryte or Selenite variant)
Barium Sulfate (BaSO4) or Gypsum (CaSO4·2H2O) with Sand inclusions
mineral
Petrified Wood (Silicified Wood)
Silicified Wood (primarily Chalcedony/Quartz, SiO2)
mineral
Petrified Wood
Silicified Wood (SiO2)
mineral
Red Sandstone
Arenite (primarily Quartz and Feldspar with Iron Oxide cement)
sedimentary
Concretion or Geode (unbroken)
Varied (depending on mineral composition and cementing agent). For quartz-lined geodes, the scientific name of the dominant mineral would be Quartz (SiO2). For calcite-lined geodes, Calcite (CaCO3). Concretions are often composed of cryptocrystalline quartz (chert), calcite, or iron oxides.
Sedimentary rock (specifically a concretion or possibly a geode)
Amber
Succinite (a Fossilized Tree Resin); Chemical formula is approximately C10H16O
Organic mineraloid
Petrified Wood
Silicified wood (Quartz/Chalcedony)
Sedimentary