Rock Identifier

Category

Organic Gemstone (Sedimentary Classification)

Browse organic gemstone (sedimentary classification) specimens identified by the Rock Identifier community.

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

Prehnite

Prehnite (Ca2Al(AlSi3O10)(OH)2)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

Pink Feldspar (Orthoclase) (Orthoclase Feldspar (KAlSi3O8)) — mineral

Pink Feldspar (Orthoclase)

Orthoclase Feldspar (KAlSi3O8)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Banded Agate (Agate (Silicon Dioxide - SiO2)) — mineral

Banded Agate

Agate (Silicon Dioxide - SiO2)

Tahitian Black Pearl (Biogenic Calcium Carbonate (Aragonite/Conchiolin Mixture), CaCO3) — mineral

Tahitian Black Pearl

Biogenic Calcium Carbonate (Aragonite/Conchiolin Mixture), CaCO3

Tiger's Eye (Gold/Brown variety) (Silicon dioxide (SiO2) with fibrous crocidolite inclusions) — metamorphic

Tiger's Eye (Gold/Brown variety)

Silicon dioxide (SiO2) with fibrous crocidolite inclusions

Fluorite (Calcium fluoride (CaF2)) — mineral

Fluorite

Calcium fluoride (CaF2)

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

Citrine Quartz

Silicon Dioxide (SiO2) with iron impurities

Yellow Quartz (Citrine/Lemon Quartz) (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz (Citrine/Lemon Quartz)

Silicon Dioxide (SiO2)

Malachite (Copper carbonate hydroxide, Cu2CO3(OH)2) — mineral

Malachite

Copper carbonate hydroxide, Cu2CO3(OH)2

Blue Sapphire (Corundum (Al2O3) with traces of Iron and Titanium) — mineral

Blue Sapphire

Corundum (Al2O3) with traces of Iron and Titanium

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

Amethyst

Silicon Dioxide (SiO2) containing Iron impurities

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Morganite (Pink Beryl) (Beryllium aluminum silicate Be3Al2(SiO3)6) — mineral

Morganite (Pink Beryl)

Beryllium aluminum silicate Be3Al2(SiO3)6

Amazonite with Smoky Quartz and Feldspar (Microcline (KAlSi3O8) with Quartz (SiO2)) — mineral

Amazonite with Smoky Quartz and Feldspar

Microcline (KAlSi3O8) with Quartz (SiO2)

Tiger's Eye (Silicon Dioxide (SiO2) with Limonite/Goethite pseudomorphs after Crocidolite) — Mineral

Tiger's Eye

Silicon Dioxide (SiO2) with Limonite/Goethite pseudomorphs after Crocidolite

Chlorastrolite (Greenstone) (Chlorastrolite (variety of Pumpellyite) - Ca2(Mg,Fe)Al2(SiO4)(Si2O7)(OH)2 · H2O) — mineral

Chlorastrolite (Greenstone)

Chlorastrolite (variety of Pumpellyite) - Ca2(Mg,Fe)Al2(SiO4)(Si2O7)(OH)2 · H2O

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

Milk Quartz (or Milky Quartz)

Silicon Dioxide (SiO2)

Citrine (Silicon Dioxide (SiO2)) — Mineral

Citrine

Silicon Dioxide (SiO2)

Lapis Lazuli (Lazurite-rich metamorphic rock (complex silicate)) — metamorphic

Lapis Lazuli

Lazurite-rich metamorphic rock (complex silicate)

Carnelian (Silicon Dioxide (SiO2) - variety of Chalcedony) — mineral

Carnelian

Silicon Dioxide (SiO2) - variety of Chalcedony

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)

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)

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)

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

Blue Quartzite

Silicon Dioxide (SiO2) with inclusions

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

Green Aventurine

Silicon Dioxide (SiO2) with inclusions of Fuchsite

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)

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

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)