Rock Identifier

Category

Organic Gemstone (Often Associated With Sedimentary Sequences)

Browse organic gemstone (often associated with sedimentary sequences) specimens identified by the Rock Identifier community.

Petrified Wood (Silicified wood (Quartz, SiO2)) — metamorphic

Petrified Wood

Silicified wood (Quartz, SiO2)

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

Chert (Smooth River Pebble)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Fossil Coral (Favosites Honeycomb) (Favosites (Genus), Phylum Cnidaria, Class Anthozoa) — sedimentary

Fossil Coral (Favosites Honeycomb)

Favosites (Genus), Phylum Cnidaria, Class Anthozoa

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Jasper (Iron-stained Chert) (Silicon Dioxide (SiO2) with impurities of Hematite or Goethite) — sedimentary

Jasper (Iron-stained Chert)

Silicon Dioxide (SiO2) with impurities of Hematite or Goethite

Granite (Granite) — igneous

Granite

Granite

Shale (Shale (Consolidated fine-grained clay/silt)) — sedimentary

Shale

Shale (Consolidated fine-grained clay/silt)

White Topaz (Aluminum Silicate Fluoride Hydroxide; Al2SiO4(F,OH)2) — mineral

White Topaz

Aluminum Silicate Fluoride Hydroxide; Al2SiO4(F,OH)2

Quartz (Milky Quartz) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Scoria (Lava Rock) (Vesicular Basalt / Scoria) — igneous

Scoria (Lava Rock)

Vesicular Basalt / Scoria

Shale (Fissile Mudstone (primarily composed of phyllosilicate minerals like kaolinite, montmorillonite, and illite)) — sedimentary

Shale

Fissile Mudstone (primarily composed of phyllosilicate minerals like kaolinite, montmorillonite, and illite)

Quartz (Quartz (SiO₂)) — Mineral

Quartz

Quartz (SiO₂)

Prehnite (Prehnite - Ca2Al(AlSi3O10)(OH)2) — mineral

Prehnite

Prehnite - Ca2Al(AlSi3O10)(OH)2

Green Quartzite (Meta-quartzite with Fuchsite inclusions (K(Al,Cr)2(AlSi3O10)(OH)2 + SiO2)) — metamorphic

Green Quartzite

Meta-quartzite with Fuchsite inclusions (K(Al,Cr)2(AlSi3O10)(OH)2 + SiO2)

Smoky Quartz (Smoky Quartz (Silicon Dioxide, SiO2)) — mineral

Smoky Quartz

Smoky Quartz (Silicon Dioxide, SiO2)

Sandstone Concretion (Sedimentary concretion) — Sedimentary

Sandstone Concretion

Sedimentary concretion

Citrine (Silicon Dioxide (SiO2) with iron impurities) — Mineral

Citrine

Silicon Dioxide (SiO2) with iron impurities

Sandstone (Quartz Sandstone (predominantly)) — Sedimentary

Sandstone

Quartz Sandstone (predominantly)

Grey and White Chert (Flint) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Grey and White Chert (Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Sodalite (blue beads) and Clear Quartz (clear beads) (Sodalite: Na4Al3Si3O12Cl; Quartz: SiO2) — mineral

Sodalite (blue beads) and Clear Quartz (clear beads)

Sodalite: Na4Al3Si3O12Cl; Quartz: SiO2

Pallasite Meteorite (Pallasite (ST-class)) — mineral

Pallasite Meteorite

Pallasite (ST-class)

Citrine (Silicon Dioxide (SiO2)) — mineral

Citrine

Silicon Dioxide (SiO2)

Chrysocolla (Hydrated copper silicate (Cu,Al)2H2Si2O5(OH)4·nH2O) — mineral

Chrysocolla

Hydrated copper silicate (Cu,Al)2H2Si2O5(OH)4·nH2O

Quartz (Pale Rose or Milky Variety) (Silicon Dioxide (SiO2)) — mineral

Quartz (Pale Rose or Milky Variety)

Silicon Dioxide (SiO2)

Kyanite (Kyanite (Al2SiO5)) — mineral

Kyanite

Kyanite (Al2SiO5)

Rough Emerald (Beryl (Be3Al2(SiO3)6 with Chromium/Vanadium impurities)) — mineral

Rough Emerald

Beryl (Be3Al2(SiO3)6 with Chromium/Vanadium impurities)

Mixed Tumbled Gemstones and River Rocks (Mixed Decorative Stones (predominantly Silicon Dioxide - SiO2 variants)) — Mixed (Igneous, Sedimentary, Metamorphic, and Minerals)

Mixed Tumbled Gemstones and River Rocks

Mixed Decorative Stones (predominantly Silicon Dioxide - SiO2 variants)

Mixed (Igneous, Sedimentary, Metamorphic, and Minerals)

Coal (specifically Bituminous or Anthracite) (Organic sedimentary rock; primarily Carbon (C) with varying H, S, O, N) — sedimentary

Coal (specifically Bituminous or Anthracite)

Organic sedimentary rock; primarily Carbon (C) with varying H, S, O, N

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

Banded Chert (Jasper)

Silicon Dioxide (SiO2)

Banded Gneiss (River Rock/Pebble) (Gneiss (specifically a banded variety, likely a orthogneiss or paragneiss depending on parent rock)) — Metamorphic Rock

Banded Gneiss (River Rock/Pebble)

Gneiss (specifically a banded variety, likely a orthogneiss or paragneiss depending on parent rock)

Metamorphic Rock

Sunstone and Green Aventurine (Sunstone: (Ca,Na)[(Al,Si)2Si2O8] (Plagioclase Feldspar Group); Green Aventurine: SiO2 (Quartz)) — Mineral

Sunstone and Green Aventurine

Sunstone: (Ca,Na)[(Al,Si)2Si2O8] (Plagioclase Feldspar Group); Green Aventurine: SiO2 (Quartz)

Septarian Nodule (Septarian Concretion (CaCO3 with Siderite/Calcite/Aragonite)) — sedimentary

Septarian Nodule

Septarian Concretion (CaCO3 with Siderite/Calcite/Aragonite)

Chert (Hag Stone / Hole Stone) (Chert (Cryptocrystalline variety of Quartz, SiO2)) — sedimentary

Chert (Hag Stone / Hole Stone)

Chert (Cryptocrystalline variety of Quartz, SiO2)

Shale (Lutaceous sedimentary rock) — sedimentary

Shale

Lutaceous sedimentary rock

Petrified Wood (Silicified Wood (SiO2 - Silicon Dioxide)) — mineral

Petrified Wood

Silicified Wood (SiO2 - Silicon Dioxide)

Petrified Wood (Silicified Wood (SiO2 - Silicon Dioxide)) — mineral

Petrified Wood

Silicified Wood (SiO2 - Silicon Dioxide)

Asphalt (Bituminous pavement) (Bituminous concrete / Asphalt) — Sedimentary (Anthropogenic)

Asphalt (Bituminous pavement)

Bituminous concrete / Asphalt

Sedimentary (Anthropogenic)

Chalcedony (Botryoidal/Tumbled Agate) (Silicon Dioxide (SiO2)) — mineral

Chalcedony (Botryoidal/Tumbled Agate)

Silicon Dioxide (SiO2)

Botryoidal Hematite (Iron Ore) (Iron(III) oxide (Fe2O3)) — mineral

Botryoidal Hematite (Iron Ore)

Iron(III) oxide (Fe2O3)

Pink Garnet (likely Almandine or Rhodolite) (Garnet Group (Fe3Al2(SiO4)3 to Mg3Al2(SiO4)3)) — mineral

Pink Garnet (likely Almandine or Rhodolite)

Garnet Group (Fe3Al2(SiO4)3 to Mg3Al2(SiO4)3)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)