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.

Fluorite (Calcium Fluoride (CaF2)) — mineral

Fluorite

Calcium Fluoride (CaF2)

Red Jasper (Jasper (Silicon Dioxide with Iron Oxide impurities), formula: SiO2) — mineral

Red Jasper

Jasper (Silicon Dioxide with Iron Oxide impurities), formula: SiO2

Obsidian (Volcanic glass (Mainly SiO2)) — igneous

Obsidian

Volcanic glass (Mainly SiO2)

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

Almandine Garnet

Almandine (Fe3Al2(SiO4)3)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Picture Jasper (Silicified sedimentary or volcanic rock (primarily SiO2)) — sedimentary

Picture Jasper

Silicified sedimentary or volcanic rock (primarily SiO2)

Red Jasper (Heliotrope family variant) (Silicon Dioxide with Hematite inclusions (SiO2 + Fe2O3)) — sedimentary

Red Jasper (Heliotrope family variant)

Silicon Dioxide with Hematite inclusions (SiO2 + Fe2O3)

Peach Moonstone (Moonstone (KAlSi3O8)) — mineral

Peach Moonstone

Moonstone (KAlSi3O8)

Chalcedony (Quartz Var.) (Silicon Dioxide (SiO2)) — mineral

Chalcedony (Quartz Var.)

Silicon Dioxide (SiO2)

Chert (Jasper/Common Opal mix) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper/Common Opal mix)

Microcrystalline Quartz (SiO2)

Chert (Yellow Jasper variant) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Yellow Jasper variant)

Silicon Dioxide (SiO2)

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

Chert (Flint)

Microcrystalline or Cryptocrystalline 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)

Aquamarine (Beryl (Be3Al2Si6O18), specifically the blue-green variety) — Mineral

Aquamarine

Beryl (Be3Al2Si6O18), specifically the blue-green variety

Travertine (used in construction, not a 'specimen' in situ) (Travertine) — Sedimentary

Travertine (used in construction, not a 'specimen' in situ)

Travertine

Slate (Slate (Metamorphic Rock)) — metamorphic

Slate

Slate (Metamorphic Rock)

Jasper (Silicon Dioxide (SiO2)) — mineral

Jasper

Silicon Dioxide (SiO2)

Jasper (Silicon dioxide (SiO2) with iron oxide inclusions) — sedimentary

Jasper

Silicon dioxide (SiO2) with iron oxide inclusions

Amazonite (Potassium Feldspar (Microcline) - K(AlSi3O8)) — mineral

Amazonite

Potassium Feldspar (Microcline) - K(AlSi3O8)

Bituminous Coal (Organic-rich sedimentary rock (Complex hydrocarbons)) — sedimentary

Bituminous Coal

Organic-rich sedimentary rock (Complex hydrocarbons)

Chert (Arrowhead Preform) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (Arrowhead Preform)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Ammolite (Ammolite (Biogenic Aragonite with trace elements; fossils of Placenticeras meeki and Placenticeras intercalare)) — mineral

Ammolite

Ammolite (Biogenic Aragonite with trace elements; fossils of Placenticeras meeki and Placenticeras intercalare)

Opalite (Synthetic Opalite Glass (Silicon Dioxide)) — mineraloid (man-made)

Opalite

Synthetic Opalite Glass (Silicon Dioxide)

mineraloid (man-made)

Moss Agate (Silicon Dioxide (SiO2) with inclusions of manganese or iron oxide) — mineral

Moss Agate

Silicon Dioxide (SiO2) with inclusions of manganese or iron oxide

Quartz (Silicon dioxide (SiO2)) — Mineral

Quartz

Silicon dioxide (SiO2)

Yellow Jade (Nephrite or Quartzite variety) (Ca2(Mg,Fe)5Si8O22(OH)2 (Nephrite) / SiO2 (Quartzite variant)) — metamorphic

Yellow Jade (Nephrite or Quartzite variety)

Ca2(Mg,Fe)5Si8O22(OH)2 (Nephrite) / SiO2 (Quartzite variant)

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

Almandine Garnet

Almandine (Fe3Al2(SiO4)3)

Jasper (Silicon dioxide (SiO2)) — sedimentary

Jasper

Silicon dioxide (SiO2)

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

Chert (Flint/Chalcedony)

Microcrystalline Quartz (SiO2)

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

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

Bivalve Fossil (Internal Mold/Steinkern) (Class Bivalvia (Fossilized Mold)) — sedimentary

Bivalve Fossil (Internal Mold/Steinkern)

Class Bivalvia (Fossilized Mold)

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

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Black Jasper (Black Onyx substitute) (Silicon Dioxide (SiO2) with carbonaceous impurities) — sedimentary (microcrystalline quartz)

Black Jasper (Black Onyx substitute)

Silicon Dioxide (SiO2) with carbonaceous impurities

sedimentary (microcrystalline quartz)

Schist (Mica Schist) — metamorphic

Schist

Mica Schist

Amber (Succinite (fossilized resin)) — mineral

Amber

Succinite (fossilized resin)

Jasper (Iron-rich Chalcedony) (Jasper (Microcrystalline Silicon Dioxide, SiO2 plus iron oxide impurities)) — Sedimentary / Metamorphic

Jasper (Iron-rich Chalcedony)

Jasper (Microcrystalline Silicon Dioxide, SiO2 plus iron oxide impurities)

Sedimentary / Metamorphic

Greenstone / Epidosite (Epidosite (Metasomatic rock consisting mainly of Epidite Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH) and Quartz)) — metamorphic

Greenstone / Epidosite

Epidosite (Metasomatic rock consisting mainly of Epidite Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH) and Quartz)

Anthracite Coal (Anthracite) — metamorphic

Anthracite Coal

Anthracite

Gneiss (Gneiss) — metamorphic

Gneiss

Gneiss

Red Granite (Phaneritic Felsic Intrusive Igneous Rock (primarily K-feldspar, Quartz, and Biotite)) — igneous

Red Granite

Phaneritic Felsic Intrusive Igneous Rock (primarily K-feldspar, Quartz, and Biotite)

Gold (Native Gold (Au)) — mineral

Gold

Native Gold (Au)

Porphyry (Porphyritic Basalt/Andesite) — igneous

Porphyry

Porphyritic Basalt/Andesite