Tektite (specifically Indochinite)
Tektite (Natural silica glass)
Mineraloid (Impact glass)
Category
Man Made Byproduct (Often Mistaken For Obsidian Or Emerald)
Browse man made byproduct (often mistaken for obsidian or emerald) specimens identified by the Rock Identifier community.
Snowflake Obsidian
Volcanic glass with Cristobalite inclusions (70–75% SiO2)
Igneous
Apache Tear
Obsidian (Hydrated Volcanic Glass - SiO2)
igneous
Sodalite
Sodalite (Na8Al6Si6O24Cl2)
mineral
Amazonite
KAlSi3O8 (Potassium Aluminum Silicate)
mineral
Black Spinel
Magnesium Aluminum Oxide (MgAl2O4)
mineral
Quartzite
Quartzite (primarily SiO2)
metamorphic
Sodalite
Sodalite (Na8Al6Si6O24Cl2)
mineral
Chert (often called Flint)
Chert (Cryptocrystalline Quartz, SiO2)
sedimentary
Ferruginous Sandstone (Ironstone Nodules)
Ferruginous Quartz-Arenite (with Goethite/Hematite cement)
sedimentary
Black Chert
Chert (microcrystalline quartz)
Mineral
Yellow Quartz (Citrine/Yellow Jasper)
Silicon Dioxide (SiO2)
mineral
Mixed Tumbled Gemstones (Agate, Aventurine, Pyrite, etc.)
Multiple (principally Silicon Dioxide SiO2 and Iron Disulfide FeS2)
mineral
Quartz with Iron Staining
Silicon Dioxide (SiO2) with iron oxide impurities
mineral
Quartzite
Quartzite (primarily SiO2)
metamorphic
Quartzite
Quartzite (primarily SiO2)
metamorphic
Quartzite
Quartzite (SiO2)
metamorphic
Flint (or Chert)
Cryptocrystalline Quartz (SiO2)
sedimentary
Green Aventurine
Silicon Dioxide (SiO2) with Fuchsite inclusions
metamorphic
Lapis Lazuli
Lapis Lazuli (Complex aggregate of Lazurite, Calcite, and Pyrite)
metamorphic
Pink Quartzite
Quartzite (primarily SiO2)
metamorphic
Pumice
Pumicite (Amorphous glass with varying chemical composition, often rhyolitic)
Igneous
Granite Pebble
Felsic intrusive igneous rock
igneous
Man-made Ceramic / Clay Figurine
Aluminosilicate Ceramic (Processed Clay)
Synthetic (not a rock or mineral)
Ironstone Concretion / Limonite Node
Goethite and Limonite (FeO(OH) nH2O)
sedimentary
Ferruginous Quartz
Silicon Dioxide (SiO2) with Hematite/Limonite impurities
mineral
Ironstone Concretion (Limonite/Goethite)
Goethite-rich Concretion (FeO(OH))
sedimentary
Fossilized Brachiopod
Brachiopoda (Class Rhynchonellata or Spiriferida)
sedimentary
Chrysoprase
Silicon dioxide with nickel impurities (SiO2 + Ni)
mineral
Chert
Microcrystalline Quartz (SiO2)
sedimentary
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
mineral
Faceted Glass (Costume Jewelry)
Amorphous Silicon Dioxide with colorants (Glass)
Synthetic/Man-made Material
Dolerite (Diabase)
Dolerite / Diabase
igneous
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Liesegang Ring Siltstone
Siltstone with iron oxide Liesegang bands
sedimentary
Sodalite
Sodalite (Na8(Al6Si6O24)Cl2)
mineral
Diorite
Diorite (Intermediate intrusive igneous rock)
igneous
Granodiorite
Granodiorite (Quartz + Plagioclase + Alkali Feldspar + Biotite/Hornblende)
igneous
Muscovite Schist
Muscovite Mica Schist (KAl2(AlSi3O10)(OH)2)
metamorphic
Sodalite
Sodalite - Na8(Al6Si6O24)Cl2
mineral
Ironstone Concretion (Limonite/Hematite Nodules)
Ironstone (principally Limonite FeO(OH)·nH2O or Hematite Fe2O3 mixed with silica/clay)
sedimentary
Chert / Flint
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary