Mahogany Obsidian
Volcanic glass (SiO2 with Hematite or Magnetite inclusions)
igneous
Category
Mineral (Specifically A Mineraloid)
Browse mineral (specifically a mineraloid) specimens identified by the Rock Identifier community.
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Conglomerate
Polymictic Conglomerate
sedimentary
Ventifact
Wind-abraded rock (Ventifact)
sedimentary
Ocean Jasper
Silicon Dioxide (SiO2) with various inclusions
sedimentary
Yellow Jasper
Silicon Dioxide (SiO2)
sedimentary
Yellow Jasper
Silicon Dioxide (SiO2) with Iron inclusions
sedimentary
Chert (containing Flint nodules)
Microcrystalline or cryptocrystalline Quartz (SiO2)
sedimentary
Vesicular Basalt (Scoria)
Mafic extrusive igneous rock (primarily Plagioclase Feldspar and Pyroxene)
igneous
Pink Granite
Phaneritic Felsic Intrusive Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)
igneous
Pyritic Shale
Carbonaceous Shale with Iron Pyrite (FeS2)
sedimentary
Chert / Flint
Microcrystalline quartz (SiO2)
sedimentary
Epidote (Unakite variety)
Epidosite (Metasomatic rock containing Ca2(Al,Fe)3(SiO4)3(OH))
metamorphic
Yellow Jasper
Silicon Dioxide (SiO2) with iron oxide impurities
sedimentary
Ruby (faceted gemstone)
Corundum (Al2O3 with Cr impurities)
gemstone
Flint Pebble
Sedimentary cryptocrystalline quartz (SiO2)
sedimentary
Synthetic Faux Fur Fursuit
Polyacrylonitrile / Polyester (Synthetic Textile)
not a rock (synthetic material/costume)
Red Jasper
Microcrystalline Quartz (SiO2) with iron oxide inclusions
sedimentary
Pink Granite
Granite (Alkali-feldspar granite)
igneous
Fancy Jasper
Silicon dioxide (SiO2)
sedimentary
Ventifact
Eolian Ventifact (often composed of basalt, chert, or quartzite)
sedimentary
Yellow Jasper
Silicon Dioxide (SiO2) with iron hydroxides
sedimentary
Flint
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Flint) Nodule
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Green Quartzite (with Fuchsite)
Quartzite with Muscovite variety Fuchsite (K(Al,Cr)2(AlSi3O10)(OH)2)
metamorphic
Pink Granite (Water-worn Cobble)
Phaneritic Felsic Intrusive Igneous Rock
igneous
Granite featuring Quartz Vein
Phaneritic Felsic Igneous Rock (Quartz, Orthoclase Feldspar, Mica)
igneous
Yellow Jasper
Silicon Dioxide (SiO2) with Goethite or Limonite inclusions
sedimentary
Flint
Microcrystalline quartz (SiO2)
sedimentary
Yellow Jasper
Silicon Dioxide (SiO2) with iron hydroxides (Goethite)
sedimentary
Red Granite
Phaneritic Plutonic Felsic Rock (rich in Potassium Feldspar)
igneous
Red Jasper (Brecciated or Mottled)
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary
Chert (Black Chert/Flint)
Microcrystalline quartz (SiO2)
sedimentary
Jasper Chert
Microcrystalline Quartz (SiO2) with iron oxide inclusions
sedimentary
Yellow Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary
Yellow Jasper
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Green Jasper with Agate Banding
Silicon Dioxide (SiO2) with impurities of ferrous silicate or chlorite
sedimentary (chemical/biological origin)
Pink Granite
Granite (Felsic Plutonic Rock)
igneous
Chert Pebble
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Jasper focus)
Silicon dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Diabase
Diabase (also known as Dolerite)
igneous
Fossil Coral
Tabulate Coral (potentially Favosites or Calapoecia)
fossil
Red Jasper (possibly banded Jaspilite)
Silicon Dioxide with Iron Oxide (SiO2 + Fe2O3)
sedimentary