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.

Learn about Organic Gemstone (Often Associated With Sedimentary Sequences) in the encyclopedia

Sapropel

Bituminous Shale

Bituminous Shale

Turbidite

Black Shale

Ironstone

Oil Shale

Jet

Limestone

Sandstone

Pegmatite

Euxenite

Pyroxenite

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

Unakite (Epidotized Granite) — metamorphic

Unakite

Epidotized Granite

Chert (and Flint variant) (Chert (SiO2)) — sedimentary

Chert (and Flint variant)

Chert (SiO2)

Chert Arrowhead (Projectile Point) (Microcrystalline Quartz (Chert or Flint)) — sedimentary

Chert Arrowhead (Projectile Point)

Microcrystalline Quartz (Chert or Flint)

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)

$Black Tourmaline (Schorl (Na(Fe2+)_{3}Al_{6} (BO_{3})_{3} (Si_{6}O_{18})(OH)_{4})) — Mineral$

Black Tourmaline

Schorl (Na(Fe2+)_{3}Al_{6} (BO_{3})_{3} (Si_{6}O_{18})(OH)_{4})

Blue Apatite (Fluoroapatite (Ca5(PO4)3F)) — mineral

Blue Apatite

Fluoroapatite (Ca5(PO4)3F)

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Green Fluorite (Calcium Fluoride (CaF2)) — mineral

Green Fluorite

Calcium Fluoride (CaF2)

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

Chert (Iron-stained)

Chert (primarily Microcrystalline Quartz, SiO2)

Gneiss (Gneiss (quartz-feldspar-biotite gneiss)) — metamorphic

Gneiss

Gneiss (quartz-feldspar-biotite gneiss)

Chert (specifically Green Chert/Jasper) (Silicon Dioxide (SiO2) - Cryptocrystalline Quartz) — sedimentary

Chert (specifically Green Chert/Jasper)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Petrified Wood (Silicified Wood (primarily Quartz/Chalcedony, SiO2)) — fossil

Petrified Wood

Silicified Wood (primarily Quartz/Chalcedony, SiO2)

Jasper (Jasper (Silicon Dioxide, SiO2)) — sedimentary

Jasper

Jasper (Silicon Dioxide, SiO2)

Red Jasper (Silicon Dioxide with Iron inclusions (SiO2)) — sedimentary

Red Jasper

Silicon Dioxide with Iron inclusions (SiO2)

Chert (and/or Siltstone River Pebble) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (and/or Siltstone River Pebble)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

African Turquoise (Jasper) (Polychrome African Jasper (often marketed as 'African Turquoise' due to its color, but it is not true turquoise)) — Rock

African Turquoise (Jasper)

Polychrome African Jasper (often marketed as 'African Turquoise' due to its color, but it is not true turquoise)

Amber (Succinates (Organic Fossilized Resin)) — mineraloid

Amber

Succinates (Organic Fossilized Resin)

Jasper (Microcrystalline Quartz (SiO2)) — sedimentary

Jasper

Microcrystalline Quartz (SiO2)

Turquoise (likely stabilized or simulated Howlite) (CuAl6(PO4)4(OH)8·4H2O (Hydrous phosphate of copper and aluminium)) — mineral

Turquoise (likely stabilized or simulated Howlite)

CuAl6(PO4)4(OH)8·4H2O (Hydrous phosphate of copper and aluminium)

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

Agate (Chert/Chalcedony)

Silicon Dioxide (SiO2)

Lazulite (Lazulite (Mg,Fe2+)Al2(PO4)2(OH)2) — mineral

Lazulite

Lazulite (Mg,Fe2+)Al2(PO4)2(OH)2

Petrified Wood (Agatized/Silicified Wood) (Silicified Wood / Chalcedony (SiO2)) — sedimentary

Petrified Wood (Agatized/Silicified Wood)

Silicified Wood / Chalcedony (SiO2)

Petrified Wood (Silicified wood (Quartz, Chalcedony, or Opal)) — sedimentary

Petrified Wood

Silicified wood (Quartz, Chalcedony, or Opal)

Epidote (or Epidote-rich rock) (Epidote. Mineral formula: Ca2(Al,Fe)3(SiO4)3(OH).) — Mineral, often found in metamorphic rocks but also in sedimentary and igneous rocks

Epidote (or Epidote-rich rock)

Epidote. Mineral formula: Ca2(Al,Fe)3(SiO4)3(OH).

Mineral, often found in metamorphic rocks but also in sedimentary and igneous rocks

Turquoise (CuAl6(PO4)4(OH)8·4H2O (Hydrated copper and aluminium phosphate)) — mineral

Turquoise

CuAl6(PO4)4(OH)8·4H2O (Hydrated copper and aluminium phosphate)

Chert (often called Flint) (Silicon Dioxide (SiO2)) — sedimentary

Chert (often called Flint)

Silicon Dioxide (SiO2)

Serpentine (Antigorite-Lizardite-Chrysotile (Mg3Si2O5(OH)4)) — metamorphic

Serpentine

Antigorite-Lizardite-Chrysotile (Mg3Si2O5(OH)4)

Jade (Nephrite or Jadeite) (Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2) or Jadeite (Na(Al,Fe3+)Si2O6)) — Metamorphic Rock / Mineral

Jade (Nephrite or Jadeite)

Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2) or Jadeite (Na(Al,Fe3+)Si2O6)

Metamorphic Rock / Mineral

Yellow or Honey Quartz (Silicon Dioxide (SiO2)) — mineral

Yellow or Honey Quartz

Silicon Dioxide (SiO2)

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

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Amber (Succinite / Fossilized Tree Resin) — fossil

Amber

Succinite / Fossilized Tree Resin

Chert (Nodule / Geode fragment) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Nodule / Geode fragment)

Microcrystalline Quartz (SiO2)

Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

Red Jasper (Microcrystalline Quartz (SiO2 with Iron Oxide impurities)) — sedimentary

Red Jasper

Microcrystalline Quartz (SiO2 with Iron Oxide impurities)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Dinosaur Bone (Agatized Dinosaur Bone) — sedimentary/fossil

Dinosaur Bone

Agatized Dinosaur Bone

sedimentary/fossil

Demantoid Garnet on Matrix (Demantoid (variety of Andradite Garnet) - Ca3(Fe3+)2(SiO4)3) — mineral

Demantoid Garnet on Matrix

Demantoid (variety of Andradite Garnet) - Ca3(Fe3+)2(SiO4)3

Chert (variations include Flint) (Chert (Silicon Dioxide, SiO2)) — sedimentary

Chert (variations include Flint)

Chert (Silicon Dioxide, SiO2)

Chert (River Pebble) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (River Pebble)

Microcrystalline Quartz (SiO2)

Fluorite (Fluorite (Calcium Fluoride, CaF2)) — Mineral

Fluorite

Fluorite (Calcium Fluoride, CaF2)

Likely tumbled jasper or chert specimens (Microcrystalline quartz (SiO₂), commonly jasper/chert; exact identification is uncertain from the photograph) — sedimentary

Likely tumbled jasper or chert specimens

Microcrystalline quartz (SiO₂), commonly jasper/chert; exact identification is uncertain from the photograph