Rock Identifier

Category

Organic Gemstone (Not A Rock Or Mineral In The Traditional Sense, But Bio Mineralized Material)

Browse organic gemstone (not a rock or mineral in the traditional sense, but bio mineralized material) specimens identified by the Rock Identifier community.

Limonite (Iron Ore) (Limonite (FeO(OH)·nH2O)) — mineral

Limonite (Iron Ore)

Limonite (FeO(OH)·nH2O)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Quartz (Quartz (SiO₂ - Silicon Dioxide)) — Mineral

Quartz

Quartz (SiO₂ - Silicon Dioxide)

Petrified Wood (Silicified wood (primarily Silicon Dioxide, SiO2)) — sedimentary

Petrified Wood

Silicified wood (primarily Silicon Dioxide, SiO2)

Vesicular Basalt (Scoria) (Basalt (Extrusive Igneous Rock)) — igneous

Vesicular Basalt (Scoria)

Basalt (Extrusive Igneous Rock)

Glauconitic Sandstone (Greensand) (Glauconitic Quartz Arenite (containing Glauconite, (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)) — sedimentary

Glauconitic Sandstone (Greensand)

Glauconitic Quartz Arenite (containing Glauconite, (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)

Clay Brick (Ceramic structural unit (Al2O3·2SiO2·2H2O as precursor)) — metamorphic (man-made/anthropogenic)

Clay Brick

Ceramic structural unit (Al2O3·2SiO2·2H2O as precursor)

metamorphic (man-made/anthropogenic)

Red Jasper (Quartz (Silicon Dioxide) with Hematite inclusions, SiO2) — mineral

Red Jasper

Quartz (Silicon Dioxide) with Hematite inclusions, SiO2

Sandstone (with potential mineral staining/concretions) (Arenite (SiO2 based)) — sedimentary

Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

Sandstone (Arenite (SiO2 principal)) — sedimentary

Sandstone

Arenite (SiO2 principal)

Granite (Granite) — igneous

Granite

Granite

Granite Sand (Decomposed Granite) (Grus / Quartz-Feldspar Detritus) — sedimentary

Granite Sand (Decomposed Granite)

Grus / Quartz-Feldspar Detritus

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Chert (with Limestone/Dolomite host) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (with Limestone/Dolomite host)

Microcrystalline Quartz (SiO2)

Geode (Unopened) (Silica-rich concretion (SiO2)) — sedimentary

Geode (Unopened)

Silica-rich concretion (SiO2)

White Jade / White Chalcedony (Nephrite Jade (Ca2(Mg,Fe)5Si8O22(OH)2) or Chalcedony (SiO2)) — Mineral

White Jade / White Chalcedony

Nephrite Jade (Ca2(Mg,Fe)5Si8O22(OH)2) or Chalcedony (SiO2)

Yellow Jasper (Jasper, a microcrystalline variety of Quartz (SiO2) with iron inclusions) — sedimentary

Yellow Jasper

Jasper, a microcrystalline variety of Quartz (SiO2) with iron inclusions

Chert / Chalcedony (Silicon Dioxide (SiO2)) — sedimentary

Chert / Chalcedony

Silicon Dioxide (SiO2)

Jasper (specifically Polychrome or Desert Jasper) (Silicon Dioxide (SiO2) with iron oxide and other mineral impurities) — sedimentary (chemical/biological origin)

Jasper (specifically Polychrome or Desert Jasper)

Silicon Dioxide (SiO2) with iron oxide and other mineral impurities

sedimentary (chemical/biological origin)

Chert (often called Flint) (Microcrystalline to cryptocrystalline quartz (SiO2)) — sedimentary

Chert (often called Flint)

Microcrystalline to cryptocrystalline quartz (SiO2)

Olivine in Basalt (Peridot) (Magnesium Iron Silicate (Mg, Fe)2SiO4 in Vesicular Basalt) — igneous

Olivine in Basalt (Peridot)

Magnesium Iron Silicate (Mg, Fe)2SiO4 in Vesicular Basalt

Sandstone (with Iron Staining) (Clastic Sedimentary Rock (primarily Quartz, SiO2)) — sedimentary

Sandstone (with Iron Staining)

Clastic Sedimentary Rock (primarily Quartz, SiO2)

Almandine Garnet (Almandine (Fe3Al2(SiO4)3)) — mineral

Almandine Garnet

Almandine (Fe3Al2(SiO4)3)

Lapis Lazuli (Sodium aluminum silicate with sulfur (main component: Lazurite [(Na,Ca)8(AlSiO4)6(SO4,S,Cl)2])) — metamorphic

Lapis Lazuli

Sodium aluminum silicate with sulfur (main component: Lazurite [(Na,Ca)8(AlSiO4)6(SO4,S,Cl)2])

Quartz (likely) / Siliceous rock with quartz phenocrysts (if a rock fragment) (Quartz (SiO₂)) — Mineral

Quartz (likely) / Siliceous rock with quartz phenocrysts (if a rock fragment)

Quartz (SiO₂)

Epidote (Epidote ({Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH))) — mineral

Epidote

Epidote ({Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH))

Bicolor Quartz Pebble (Silicon Dioxide (SiO2) with mineral inclusions) — mineral

Bicolor Quartz Pebble

Silicon Dioxide (SiO2) with mineral inclusions

Sandstone (Ferruginous) (Arenite with Iron Oxides) — sedimentary

Sandstone (Ferruginous)

Arenite with Iron Oxides

Chert (Nodular) (Chert (SiO2 - Microcrystalline Quartz)) — sedimentary

Chert (Nodular)

Chert (SiO2 - Microcrystalline Quartz)

Pearl (Calcium Carbonate (CaCO3) with Conchiolin) — mineral

Pearl

Calcium Carbonate (CaCO3) with Conchiolin

Ferruginous Sandstone (Ironstone) (Clastic sedimentary rock (SiO2 with Fe2O3/FeO(OH) cement)) — sedimentary

Ferruginous Sandstone (Ironstone)

Clastic sedimentary rock (SiO2 with Fe2O3/FeO(OH) cement)

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

Chert / Flint

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Pearl (Calcium carbonate (CaCO3) as Aragonite or Calcite) — mineral

Pearl

Calcium carbonate (CaCO3) as Aragonite or Calcite

Shale with Vein Infillings (Shale (a fine-grained clastic sedimentary rock). The veins could be Calcite (CaCO3), Quartz (SiO2), or other minerals.) — Sedimentary Rock

Shale with Vein Infillings

Shale (a fine-grained clastic sedimentary rock). The veins could be Calcite (CaCO3), Quartz (SiO2), or other minerals.

Sedimentary Rock

Sandstone (Quartzose Sandstone) (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone (Quartzose Sandstone)

Clastic sedimentary rock (primarily SiO2)

Sandstone (likely Ferruginous) (Sandstone (SiO2 with iron oxides)) — sedimentary

Sandstone (likely Ferruginous)

Sandstone (SiO2 with iron oxides)

Soapstone (Steatite (primarily composed of Talc, Mg₃Si₄O₁₀(OH)₂)) — Metamorphic Rock

Soapstone

Steatite (primarily composed of Talc, Mg₃Si₄O₁₀(OH)₂)

Metamorphic Rock

Chert (with Quartz vein/coating) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (with Quartz vein/coating)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2 - primarily Quartz/Chalcedony/Opal)) — Mineral/Fossil (Sedimentary context)

Petrified Wood

Silicified Wood (SiO2 - primarily Quartz/Chalcedony/Opal)

Mineral/Fossil (Sedimentary context)

Sandstone (Banded) (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone (Banded)

Clastic sedimentary rock (primarily SiO2)

Limonite (Iron Ore) (Limonite (FeO(OH)·nH2O)) — Mineral

Limonite (Iron Ore)

Limonite (FeO(OH)·nH2O)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)