Rock Identifier

Category

Organic Gemstone

Browse organic gemstone specimens identified by the Rock Identifier community.

Chert (containing Flint nodules) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (containing Flint nodules)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Obsidian (Obsidian (Volcanic Glass), primarily SiO2) — igneous

Obsidian

Obsidian (Volcanic Glass), primarily SiO2

Blue Tiger's Eye (Pseudomorph of Quartz after Crocidolite (SiO2 with inclusions of asbestiform silicates)) — mineral

Blue Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with inclusions of asbestiform silicates)

Greenstone (Greywacke or Nephrite Jade variant) (Metamorphosed mafic igneous or sedimentary rock (e.g., Actinolite-Chlorite Schist)) — metamorphic

Greenstone (Greywacke or Nephrite Jade variant)

Metamorphosed mafic igneous or sedimentary rock (e.g., Actinolite-Chlorite Schist)

Rough Agate/Chert Nodules (Cryptocrystalline Quartz (SiO2)) — sedimentary

Rough Agate/Chert Nodules

Cryptocrystalline Quartz (SiO2)

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

Smoky Quartz (Ferruginous Quartz)

Quartz (Silicon Dioxide, SiO2)

Red Beryl (Bixbite (Be3Al2Si6O18 with Mn3+ ions)) — mineral

Red Beryl

Bixbite (Be3Al2Si6O18 with Mn3+ ions)

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Red Jasper (Silicon Dioxide (SiO2) with Hematite impurities) — sedimentary

Red Jasper

Silicon Dioxide (SiO2) with Hematite impurities

Citrine (Citrine (Silicon Dioxide, SiO2)) — mineral

Citrine

Citrine (Silicon Dioxide, SiO2)

Obsidian (Volcanic Glass (Amorphous Silicon Dioxide)) — igneous

Obsidian

Volcanic Glass (Amorphous Silicon Dioxide)

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

Amethyst

SiO2 (Silicon Dioxide with iron impurities)

Amethyst with Marcasite accents (Amethyst (Silicon Dioxide SiO2) and Marcasite (Iron Sulfide FeS2)) — mineral

Amethyst with Marcasite accents

Amethyst (Silicon Dioxide SiO2) and Marcasite (Iron Sulfide FeS2)

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

Hematite

Iron(III) oxide (Fe2O3)

Blue Quartzite (Silicon Dioxide (SiO2) with inclusions) — metamorphic

Blue Quartzite

Silicon Dioxide (SiO2) with inclusions

Quartz (Milky or Rough Variety) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky or Rough Variety)

Silicon Dioxide (SiO2)

Green Aventurine (Silicon Dioxide (SiO2) with inclusions of Fuchsite) — Mineral

Green Aventurine

Silicon Dioxide (SiO2) with inclusions of Fuchsite

Pietersite (Brecciated Crocidolite in Quartz (Chalcedony)) — metamorphic

Pietersite

Brecciated Crocidolite in Quartz (Chalcedony)

Citrine (Silicon Dioxide (SiO2) - Yellow Quartz variety) — mineral

Citrine

Silicon Dioxide (SiO2) - Yellow Quartz variety

Peach Moonstone (Orthoclase (Potassium Aluminum Silicate), KAlSi3O8) — mineral

Peach Moonstone

Orthoclase (Potassium Aluminum Silicate), KAlSi3O8

Agate (specifically Oco or Banded Agate) (Agate (a variety of Chalcedony), SiO2 (Silicon Dioxide)) — mineral

Agate (specifically Oco or Banded Agate)

Agate (a variety of Chalcedony), SiO2 (Silicon Dioxide)

Olivine (Peridotite) (Olivine Group; (Mg, Fe)2SiO4) — igneous

Olivine (Peridotite)

Olivine Group; (Mg, Fe)2SiO4

Carnelian (Chalcedony) (Silicon Dioxide (SiO2)) — mineral

Carnelian (Chalcedony)

Silicon Dioxide (SiO2)

Yellow Quartz (Citrine Quartz Pebble) (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz (Citrine Quartz Pebble)

Silicon Dioxide (SiO2)

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

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Amazonite (Amazonite (KAlSi3O8); a green variety of Microcline feldspar) — mineral

Amazonite

Amazonite (KAlSi3O8); a green variety of Microcline feldspar

Unakite (Tumbled) (Epidotized Granite) — metamorphic

Unakite (Tumbled)

Epidotized Granite

Red Jasper (Jasper (Silicon Dioxide) - SiO2) — sedimentary

Red Jasper

Jasper (Silicon Dioxide) - SiO2

Amethyst (SiO2 (Silicon Dioxide) with Iron (Fe3+) impurities) — mineral

Amethyst

SiO2 (Silicon Dioxide) with Iron (Fe3+) impurities

Rough Citrine Quartz (Citrine (Silicon Dioxide, SiO2 with iron impurities)) — mineral

Rough Citrine Quartz

Citrine (Silicon Dioxide, SiO2 with iron impurities)

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

Smoky Quartz

Smoky Quartz (Silicon Dioxide - SiO2)

Raw Emerald (Beryl (Be3Al2Si6O18 with Chromium/Vanadium)) — mineral

Raw Emerald

Beryl (Be3Al2Si6O18 with Chromium/Vanadium)

Quartz (Milky or Iron-Stained) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky or Iron-Stained)

Silicon Dioxide (SiO2)

Bicolor Tanzanite (Zoisite (Ca2Al3(SiO4)3(OH))) — mineral

Bicolor Tanzanite

Zoisite (Ca2Al3(SiO4)3(OH))

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Quartz Geode (Cracked) (Silicon Dioxide (SiO2)) — mineral

Quartz Geode (Cracked)

Silicon Dioxide (SiO2)

Yellow Jasper (Silicon Dioxide (SiO2) with iron hydroxides (Goethite/Limonite)) — sedimentary

Yellow Jasper

Silicon Dioxide (SiO2) with iron hydroxides (Goethite/Limonite)

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

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

Green Jasper (Silicon Dioxide (SiO2) with iron silicate inclusions) — sedimentary

Green Jasper

Silicon Dioxide (SiO2) with iron silicate inclusions

Cullet Glass (Slag Glass) (Amorphous Silicon Dioxide (Industrial Byproduct)) — mineraloid

Cullet Glass (Slag Glass)

Amorphous Silicon Dioxide (Industrial Byproduct)

Blue Goldstone (Aventurine Glass) — Man-made glass (often grouped with minerals in lapidary)

Blue Goldstone

Aventurine Glass

Man-made glass (often grouped with minerals in lapidary)

Fuchsite (K(Al,Cr)2(AlSi3O10)(OH)2 (Chromium-rich Muscovite)) — mineral

Fuchsite

K(Al,Cr)2(AlSi3O10)(OH)2 (Chromium-rich Muscovite)