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.

Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

Hypersthene (Hypersthene (Enstatite variety), (Mg,Fe)SiO3) — Mineral

Hypersthene

Hypersthene (Enstatite variety), (Mg,Fe)SiO3

Red Chalcedony (likely dyed) (Chalcedony (a variety of Quartz), SiO2) — Mineral (Cryptocrystalline Quartz)

Red Chalcedony (likely dyed)

Chalcedony (a variety of Quartz), SiO2

Mineral (Cryptocrystalline Quartz)

Quartz (Quartz (SiO2)) — Mineral

Quartz

Quartz (SiO2)

Chert (Silicon dioxide (SiO2)) — sedimentary

Chert

Silicon dioxide (SiO2)

Quartz (Milky/Iron-stained) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky/Iron-stained)

Silicon Dioxide (SiO2)

Sandstone (Quartzose type) (Arenite (primarily SiO2)) — sedimentary

Sandstone (Quartzose type)

Arenite (primarily SiO2)

Ring with an Orange Inlay (N/A (Man-made object)) — Man-made Object (Ring)

Ring with an Orange Inlay

N/A (Man-made object)

Man-made Object (Ring)

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

Turquoise

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

Carnelian (SiO2 (Microcrystalline Quartz / Chalcedony)) — mineral

Carnelian

SiO2 (Microcrystalline Quartz / Chalcedony)

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

Carnelian

Carnelian (SiO2 - Silicon Dioxide)

Carnelian (Orange Chalcedony) (Silicon Dioxide (SiO2) with iron oxide impurities) — mineral

Carnelian (Orange Chalcedony)

Silicon Dioxide (SiO2) with iron oxide impurities

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

Amazonite

Potassium Feldspar (Microcline), K(AlSi3O8)

Rhodonite (Rhodonite (Mn2+SiO3)) — mineral

Rhodonite

Rhodonite (Mn2+SiO3)

Ruby (Corundum (Al2O3 with Chromium impurities)) — mineral

Ruby

Corundum (Al2O3 with Chromium impurities)

Anthracite Coal (Anthracite (Carbon-rich metamorphic coal)) — metamorphic

Anthracite Coal

Anthracite (Carbon-rich metamorphic coal)

Citrine (likely Heat-Treated Amethyst) (Silicon Dioxide (SiO2)) — mineral

Citrine (likely Heat-Treated Amethyst)

Silicon Dioxide (SiO2)

Beryl (Emerald Variety) (Beryllium aluminum silicate (Be3Al2(SiO3)6) with chromium/vanadium traces) — mineral

Beryl (Emerald Variety)

Beryllium aluminum silicate (Be3Al2(SiO3)6) with chromium/vanadium traces

Carnelian (Carnelian (SiO2)) — mineral

Carnelian

Carnelian (SiO2)

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

Petrified Wood (Silicified Wood)

Silicified Wood (primarily Chalcedony/Quartz, SiO2)

Quartz (Float/Abraded) (Quartz (SiO₂)) — Mineral

Quartz (Float/Abraded)

Quartz (SiO₂)

Carnelian Agate (Silicon Dioxide (SiO2)) — mineral

Carnelian Agate

Silicon Dioxide (SiO2)

Sandstone (Painted) (Arenite (primarily SiO2)) — sedimentary

Sandstone (Painted)

Arenite (primarily SiO2)

Sandstone (Quartzose) (Arenite (primarily SiO2)) — sedimentary

Sandstone (Quartzose)

Arenite (primarily SiO2)

Jasper and Ironstone (likely Jasperized Ironstone) (Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3)) — sedimentary

Jasper and Ironstone (likely Jasperized Ironstone)

Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3)

Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

Chert Nodule (Microcrystalline Quartz (SiO2)) — sedimentary

Chert Nodule

Microcrystalline Quartz (SiO2)

Azurite and Malachite on Matrix (Cu3(CO3)2(OH)2 (Azurite) and Cu2CO3(OH)2 (Malachite)) — mineral

Azurite and Malachite on Matrix

Cu3(CO3)2(OH)2 (Azurite) and Cu2CO3(OH)2 (Malachite)

Basalt (Basalt (extrusive igneous rock)) — Igneous

Basalt

Basalt (extrusive igneous rock)

Rutilated Quartz (Quartz (SiO2) with Rutile (TiO2) inclusions) — Mineral

Rutilated Quartz

Quartz (SiO2) with Rutile (TiO2) inclusions

Obsidian (Volcanic glass) — igneous

Obsidian

Volcanic glass

Sandstone or Mudstone (Sedimentary Rock (Sandstone/Mudstone)) — sedimentary

Sandstone or Mudstone

Sedimentary Rock (Sandstone/Mudstone)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Citrine (Silicon dioxide (SiO2)) — mineral

Citrine

Silicon dioxide (SiO2)

Clear Quartz (Silicon Dioxide (SiO2)) — mineral

Clear Quartz

Silicon Dioxide (SiO2)

Zircon (Zircon (ZrSiO4)) — Mineral

Zircon

Zircon (ZrSiO4)

Precious Opal (Hydrated Silica (SiO2·nH2O)) — mineral

Precious Opal

Hydrated Silica (SiO2·nH2O)

Chert (or possibly Flint) (Chert (variant: Flint)) — Sedimentary

Chert (or possibly Flint)

Chert (variant: Flint)

Granite (Granite (a common name for a felsic intrusive igneous rock)) — Igneous Rock

Granite

Granite (a common name for a felsic intrusive igneous rock)

Biotite Mica (Biotite (K(Mg,Fe)3AlSi3O10(F,OH)2)) — mineral

Biotite Mica

Biotite (K(Mg,Fe)3AlSi3O10(F,OH)2)

Limonite (often after Hematite or Goethite) (Limonite (FeO(OH)·nH2O)) — mineral

Limonite (often after Hematite or Goethite)

Limonite (FeO(OH)·nH2O)

Green Tourmaline (Elbaite (part of Tourmaline group), Na(Li1.5Al1.5)Al6Si6O18(BO3)3(OH)4) — mineral

Green Tourmaline

Elbaite (part of Tourmaline group), Na(Li1.5Al1.5)Al6Si6O18(BO3)3(OH)4