Rock Identifier

Category

Biogenic Material

Browse biogenic material specimens identified by the Rock Identifier community.

Learn about Biogenic Material in the encyclopedia

Peat

Diatomite

Dunite

Limonite

Diamond

Peacock Opal

Metarhyolite

Rhodochrosite

Shell Opal

Madagascar Opal

Lavender Obsidian

Electric Blue Obsidian

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

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Flint) (Chert (SiO2)) — sedimentary

Chert (Flint)

Chert (SiO2)

Chert (specifically Jasper or Flint) (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Jasper or Flint)

Cryptocrystalline Quartz (SiO2)

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

Chert (Flint) (Chert (SiO2)) — sedimentary

Chert (Flint)

Chert (SiO2)

Chert (and Limestone) River Cobble (Microcrystalline Quartz (SiO2) within Calcium Carbonate (CaCO3)) — sedimentary

Chert (and Limestone) River Cobble

Microcrystalline Quartz (SiO2) within Calcium Carbonate (CaCO3)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Chert (Jasper variety)

Microcrystalline Quartz (SiO2)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

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

Chert (Flint)

Chert (Microcrystalline Quartz, SiO2)

Aragonite Star Cluster (Aragonite (Calcium Carbonate, CaCO3)) — mineral

Aragonite Star Cluster

Aragonite (Calcium Carbonate, CaCO3)

Chert (Basanite / Jasperoid) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Basanite / Jasperoid)

Microcrystalline Quartz (SiO2)

Chert (Tan/Grey variety) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Tan/Grey variety)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Coquina with Shell Fragment (Bioclastic Limestone (composed primarily of CaCO3)) — sedimentary

Coquina with Shell Fragment

Bioclastic Limestone (composed primarily of CaCO3)

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

Chert (Green variety)

Silicon Dioxide (SiO2)

Granodiorite (Granodiorite) — igneous

Granodiorite

Granodiorite

Chert (varieties include Flint and Jasper) (Silicon Dioxide (SiO2)) — sedimentary

Chert (varieties include Flint and Jasper)

Silicon Dioxide (SiO2)

Blue Aragonite (Aragonite (Calcium Carbonate, CaCO3)) — mineral

Blue Aragonite

Aragonite (Calcium Carbonate, CaCO3)

Banded Calcite (Mexican Onyx) (Calcite (CaCO3)) — mineral

Banded Calcite (Mexican Onyx)

Calcite (CaCO3)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

Polished red jasper (Jasper, an opaque microcrystalline variety of quartz (SiO₂), colored mainly by iron oxides) — mineral

Polished red jasper

Jasper, an opaque microcrystalline variety of quartz (SiO₂), colored mainly by iron oxides

Possible iron-rich concretion or weathered ironstone (Goethite/limonite-rich ironstone; exact identification requires testing) — mineral

Possible iron-rich concretion or weathered ironstone

Goethite/limonite-rich ironstone; exact identification requires testing

Tumbled carnelian (likely chalcedony) (Carnelian, orange-red cryptocrystalline quartz (SiO₂), a variety of chalcedony) — gemstone

Tumbled carnelian (likely chalcedony)

Carnelian, orange-red cryptocrystalline quartz (SiO₂), a variety of chalcedony

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

Green Chert (Jasper)

Silicon Dioxide (SiO2)

Turquoise (CuAl6(PO4)4(OH)8·4H2O) — mineral

Turquoise

CuAl6(PO4)4(OH)8·4H2O

Likely weathered quartz-rich rock fragment (Uncertain; possibly granitic pegmatite or quartz-bearing metamorphic rock) — igneous

Likely weathered quartz-rich rock fragment

Uncertain; possibly granitic pegmatite or quartz-bearing metamorphic rock

Labradorite-bearing anorthosite (Anorthosite, chiefly plagioclase feldspar (labradorite; approximately (Ca,Na)(Al,Si)₄O₈)) — igneous

Labradorite-bearing anorthosite

Anorthosite, chiefly plagioclase feldspar (labradorite; approximately (Ca,Na)(Al,Si)₄O₈)

Bamboo Leaf Jasper (Silicified Siltstone or Jasper (SiO2)) — sedimentary

Bamboo Leaf Jasper

Silicified Siltstone or Jasper (SiO2)

Quartzite Pebble (Quartzite (SiO2)) — metamorphic

Quartzite Pebble

Quartzite (SiO2)

Sandstone-based Concrete Fragment (Cementitious Composite with Sedimentary Aggregate) — sedimentary (man-made/anthropogenic)

Sandstone-based Concrete Fragment

Cementitious Composite with Sedimentary Aggregate

sedimentary (man-made/anthropogenic)

Blue cabochon gemstone, likely sapphire (Corundum (Al₂O₃), blue variety colored mainly by iron and titanium) — gemstone

Blue cabochon gemstone, likely sapphire

Corundum (Al₂O₃), blue variety colored mainly by iron and titanium

Tumbled blue quartzite or blue chalcedony (uncertain) (Quartz-rich rock; predominantly silicon dioxide (SiO₂)) — metamorphic

Tumbled blue quartzite or blue chalcedony (uncertain)

Quartz-rich rock; predominantly silicon dioxide (SiO₂)

Blue Obsidian (Cullet Glass) (Silicon Dioxide (Amorphous Glass)) — mineral

Blue Obsidian (Cullet Glass)

Silicon Dioxide (Amorphous Glass)

Diamond (Carbon (C)) — gemstone

Diamond

Carbon (C)

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

Petrified Wood

Silicified Wood (primarily SiO2)

Quartz Vein in Siltstone (Silicon Dioxide (SiO2) within Sedimentary/Metamorphic Matrix) — metamorphic

Quartz Vein in Siltstone

Silicon Dioxide (SiO2) within Sedimentary/Metamorphic Matrix

Petrified Wood (Agatized/Silicified Wood) (Silicified Wood (SiO2)) — metamorphic

Petrified Wood (Agatized/Silicified Wood)

Silicified Wood (SiO2)

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

Petrified Wood

Silicified Wood (SiO2 permineralization)

Quartz with Iron Oxide (Silicon Dioxide (SiO2) with Fe2O3 inclusions) — mineral

Quartz with Iron Oxide

Silicon Dioxide (SiO2) with Fe2O3 inclusions

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

Petrified Wood

Silicified Wood (primarily SiO2)

Asphalt Concrete (Bituminous Concrete) — sedimentary (artificial)

Asphalt Concrete

Bituminous Concrete

sedimentary (artificial)