Rock Identifier

Category

Organic Gemstone (Not A Rock Or Mineral)

Browse organic gemstone (not a rock or mineral) specimens identified by the Rock Identifier community.

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

metamorphic
Precious Coral (Corallium rubrum (Calcium carbonate with trace carotene)) — Organic gemstone / Sedimentary mineraloid

Precious Coral

Corallium rubrum (Calcium carbonate with trace carotene)

Organic gemstone / Sedimentary mineraloid
Bituminous Coal (Organic Sedimentary Rock (Carbon-based)) — sedimentary

Bituminous Coal

Organic Sedimentary Rock (Carbon-based)

sedimentary
Quartz (Milky/Common) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky/Common)

Silicon Dioxide (SiO2)

mineral
Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

mineral
Quartz (Clear Quartz/Rock Crystal) (Silicon Dioxide (SiO2)) — mineral

Quartz (Clear Quartz/Rock Crystal)

Silicon Dioxide (SiO2)

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

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

sedimentary
Amethyst Quartz (Silicon Dioxide (SiO2) with iron impurities) — mineral

Amethyst Quartz

Silicon Dioxide (SiO2) with iron impurities

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

Clear Quartz

Silicon Dioxide (SiO2)

mineral
Amethyst (Amethyst (Silica mineral, SiO2)) — mineral

Amethyst

Amethyst (Silica mineral, SiO2)

mineral
Pearl (Calcium Carbonate (CaCO3) in the form of orthorhombic Aragonite and Conchiolin) — mineral

Pearl

Calcium Carbonate (CaCO3) in the form of orthorhombic Aragonite and Conchiolin

mineral
Clear Quartz (Rock Crystal) (Silicon Dioxide (SiO2)) — mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

mineral
Amethyst Geode (Silicon Dioxide (SiO2) - Amethyst variety of Quartz) — mineral

Amethyst Geode

Silicon Dioxide (SiO2) - Amethyst variety of Quartz

mineral
Amber (Succinite (specific to Baltic amber), fossilized tree resin) — Organic Mineraloid

Amber

Succinite (specific to Baltic amber), fossilized tree resin

Organic Mineraloid
Clear Quartz (Quartz (Silicon Dioxide, SiO2)) — mineral

Clear Quartz

Quartz (Silicon Dioxide, SiO2)

mineral
Amber Inlay Jewelry (Fossilized Resin (C10H16O)) — Organic Gemstone (Biogenic)

Amber Inlay Jewelry

Fossilized Resin (C10H16O)

Organic Gemstone (Biogenic)
Hypersthene (Hypersthene ((Mg,Fe)SiO₃)) — Mineral

Hypersthene

Hypersthene ((Mg,Fe)SiO₃)

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

Chert (often called Flint)

Chert (Silicon Dioxide, SiO2)

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

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

mineral
Amber (Succinate (Fossilized Tree Resin)) — mineraloid

Amber

Succinate (Fossilized Tree Resin)

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

Milky Quartz

Silicon Dioxide (SiO2)

mineral
Banded Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert

Microcrystalline Quartz (SiO2)

sedimentary
Quartzite (specifically Milky Quartz variety) (Quartz (SiO2)) — metamorphic

Quartzite (specifically Milky Quartz variety)

Quartz (SiO2)

metamorphic
Bituminous Coal (Bituminous coal (Organic Sedimentary Rock)) — sedimentary

Bituminous Coal

Bituminous coal (Organic Sedimentary Rock)

sedimentary
White Opal (Common) (Hydrated Silica (SiO2·nH2O)) — mineral

White Opal (Common)

Hydrated Silica (SiO2·nH2O)

mineral
Chert / Flint (Chert (Cryptocrystalline Silica, SiO2)) — sedimentary

Chert / Flint

Chert (Cryptocrystalline Silica, SiO2)

sedimentary
Agate (Silicon dioxide (SiO2)) — mineral

Agate

Silicon dioxide (SiO2)

mineral
Tumbled Carnelian and Quartz Mix (Silicon Dioxide (SiO2) with iron oxide impurities) — mineral

Tumbled Carnelian and Quartz Mix

Silicon Dioxide (SiO2) with iron oxide impurities

mineral
Amethyst (Silicon Dioxide (SiO2) with Iron impurities) — mineral

Amethyst

Silicon Dioxide (SiO2) with Iron impurities

mineral
Aquamarine (Beryl (Be3Al2Si6O18 with iron impurities)) — mineral

Aquamarine

Beryl (Be3Al2Si6O18 with iron impurities)

mineral
Chert (Iron-stained) (Microcrystalline silica (SiO2) with trace Iron oxide (Fe2O3)) — sedimentary

Chert (Iron-stained)

Microcrystalline silica (SiO2) with trace Iron oxide (Fe2O3)

sedimentary
Blue Chalcedony (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — mineral

Blue Chalcedony

Silicon Dioxide (SiO2) - Microcrystalline Quartz

mineral
Chert Pebble with Quartz Veins (Microcrystalline Quartz (SiO2)) — sedimentary

Chert Pebble with Quartz Veins

Microcrystalline Quartz (SiO2)

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

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

mineral
Tiger's Eye (Pseudomorph of Quartz after Crocidolite (SiO2 with inclusions of iron oxide)) — metamorphic

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with inclusions of iron oxide)

metamorphic
Stromatolite (Biogenic Sedimentary Rock (composed predominantly of CaCO3)) — sedimentary

Stromatolite

Biogenic Sedimentary Rock (composed predominantly of CaCO3)

sedimentary
Green Tourmaline (Verdelite (Silicate mineral); Na(Li,Al)3Al6(BO3)3Si6O18(OH)4) — mineral

Green Tourmaline

Verdelite (Silicate mineral); Na(Li,Al)3Al6(BO3)3Si6O18(OH)4

mineral
Pegmatite (Coarse-grained Igneous Rock (Granitic Pegmatite)) — igneous

Pegmatite

Coarse-grained Igneous Rock (Granitic Pegmatite)

igneous
Agate (specifically Chalcedony nodule) (Silicon Dioxide (SiO2)) — mineral

Agate (specifically Chalcedony nodule)

Silicon Dioxide (SiO2)

mineral
Granite (Phaneritic Igneous Rock (primarily Quartz, Feldspar, and Mica)) — igneous

Granite

Phaneritic Igneous Rock (primarily Quartz, Feldspar, and Mica)

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

Milky Quartz (Vein Quartz)

Silicon Dioxide (SiO2)

mineral
Olivine in Basalt (Peridotite Xenolith) (Forsterite-rich Olivine (Mg2SiO4) in Aphanitic Basalt) — igneous

Olivine in Basalt (Peridotite Xenolith)

Forsterite-rich Olivine (Mg2SiO4) in Aphanitic Basalt

igneous