Rock Identifier

Category

Organic Structure (Not A Rock)

Browse organic structure (not a rock) specimens identified by the Rock Identifier community.

Coquina (Biogenic Limestone (Calcium Carbonate - CaCO3)) — sedimentary

Coquina

Biogenic Limestone (Calcium Carbonate - CaCO3)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Chert / Flint (Chert (Microcrystalline Quartz, SiO2)) — sedimentary

Chert / Flint

Chert (Microcrystalline Quartz, SiO2)

Chert (variations include Flint or Jasper) (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (variations include Flint or Jasper)

Cryptocrystalline Quartz (SiO2)

Sandstone (likely Fossilized Wood or Concrete Simulacrum) (Arenite / Silicified Wood / Anthropogenic Concrete) — sedimentary

Sandstone (likely Fossilized Wood or Concrete Simulacrum)

Arenite / Silicified Wood / Anthropogenic Concrete

Petrified Wood (Silicified Wood (primarily SiO₂ / Silicon Dioxide)) — mineral

Petrified Wood

Silicified Wood (primarily SiO₂ / Silicon Dioxide)

Amber (Succinite (formula varies, primarily C10H16O)) — Mineraloid (Organic)

Amber

Succinite (formula varies, primarily C10H16O)

Mineraloid (Organic)

Sandstone (Pebble/Cobble) (Sandstone (arenite is a more precise term for sandstone with less than 15% matrix; this specimen appears to be a lithic or quartz arenite)) — Sedimentary

Sandstone (Pebble/Cobble)

Sandstone (arenite is a more precise term for sandstone with less than 15% matrix; this specimen appears to be a lithic or quartz arenite)

Shungite (Non-crystalline carbon (similar to anthracite coal or meta-anthracite)) — metamorphic

Shungite

Non-crystalline carbon (similar to anthracite coal or meta-anthracite)

Chert / Jasper / Agate (Chalcedony Group) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert / Jasper / Agate (Chalcedony Group)

Microcrystalline Quartz (SiO2)

Sandstone (likely Arkose or Quartz Sandstone) (Arenite (SiO2 principal component)) — sedimentary

Sandstone (likely Arkose or Quartz Sandstone)

Arenite (SiO2 principal component)

Chert (Quartz Variety) (Chert (Silicon Dioxide, SiO2)) — sedimentary

Chert (Quartz Variety)

Chert (Silicon Dioxide, SiO2)

Fossilized Bone Fragment (Permineralized Vertebrate Fossil (Hydroxyapatite replaced by Minerals)) — sedimentary

Fossilized Bone Fragment

Permineralized Vertebrate Fossil (Hydroxyapatite replaced by Minerals)

Chert (Iron-stained) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Septarian Nodule (Septarian Concretion (CaCO3 with Siderite/Limonite streaks)) — sedimentary

Septarian Nodule

Septarian Concretion (CaCO3 with Siderite/Limonite streaks)

Chert (Yellow/Brown Jasper) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Yellow/Brown Jasper)

Silicon Dioxide (SiO2)

Chert (Nodule) (Chert (composition: SiO2)) — sedimentary

Chert (Nodule)

Chert (composition: SiO2)

Chert (Jasper/Flint variety) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Flint variety) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (with Quartz veins) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (with Quartz veins)

Microcrystalline Quartz (SiO2)

Red Chert (Jasper) (Silicon Dioxide (SiO2)) — sedimentary

Red Chert (Jasper)

Silicon Dioxide (SiO2)

Chalcedony (Cryptocrystalline Quartz (SiO2)) — mineral

Chalcedony

Cryptocrystalline Quartz (SiO2)

Slate (Slate (Foliated metamorphic rock)) — metamorphic

Slate

Slate (Foliated metamorphic rock)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Fossilized Coral (Cnidaria (Anthozoa), often replaced by Calcium Carbonate (CaCO3) or Silica (SiO2)) — sedimentary

Fossilized Coral

Cnidaria (Anthozoa), often replaced by Calcium Carbonate (CaCO3) or Silica (SiO2)

Chert / Flint (Chert (Cryptocrystalline Silica, SiO2)) — sedimentary

Chert / Flint

Chert (Cryptocrystalline Silica, SiO2)

Chert Nodule (Chert (Cryptocrystalline variety of Quartz, SiO2)) — sedimentary

Chert Nodule

Chert (Cryptocrystalline variety of Quartz, SiO2)

Tree Agate (also known as Dendritic Agate) (Silicon Dioxide with inclusions (SiO2 + Mn/Fe)) — mineral

Tree Agate (also known as Dendritic Agate)

Silicon Dioxide with inclusions (SiO2 + Mn/Fe)

Calligraphy Stone (Mariam Jasper (Fossiliferous Limestone with Hematite and Iron)) — sedimentary

Calligraphy Stone

Mariam Jasper (Fossiliferous Limestone with Hematite and Iron)

Moss Agate (Chalcedony (Silicon Dioxide / SiO2)) — mineral

Moss Agate

Chalcedony (Silicon Dioxide / SiO2)

Sandstone (with carbonaceous plant fragments) (Arenite (composed primarily of SiO2)) — sedimentary

Sandstone (with carbonaceous plant fragments)

Arenite (composed primarily of SiO2)

Coral Rock (Coquina) (Biogenic Limestone (Calcium Carbonate - CaCO3)) — sedimentary

Coral Rock (Coquina)

Biogenic Limestone (Calcium Carbonate - CaCO3)

Turquoise and Red Coral (Turquoise: CuAl6(PO4)4(OH)8·4H2O; Red Coral: Corallium rubrum (organic gemstone)) — mineral

Turquoise and Red Coral

Turquoise: CuAl6(PO4)4(OH)8·4H2O; Red Coral: Corallium rubrum (organic gemstone)

Chert (often called Flint in dark varieties) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often called Flint in dark varieties)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Jasper (Silicon dioxide (SiO2)) — sedimentary

Jasper

Silicon dioxide (SiO2)

Chert (Nodule) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Nodule)

Silicon Dioxide (SiO2)

Limestone (Weathered) (Calcium Carbonate (CaCO3)) — sedimentary

Limestone (Weathered)

Calcium Carbonate (CaCO3)

Chert (Jasper variety) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Chert (Smooth River Pebble) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Smooth River Pebble)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Pyrite in Shale (Iron Sulfide (FeS2) in Sedimentary Matrix) — mineral

Pyrite in Shale

Iron Sulfide (FeS2) in Sedimentary Matrix

Chert (Jasper/Flint variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (primarily SiO2)) — sedimentary

Petrified Wood

Silicified Wood (primarily SiO2)