Ironstone Concretion (Ironstone Gourd)
Limonite/Goethite Concretion (FeOO(H))
Category
Browse metamorphic rock (specifically a rock composed of minerals) specimens identified by the Rock Identifier community.
Ironstone Concretion (Ironstone Gourd)
Limonite/Goethite Concretion (FeOO(H))
Granite
Phaneritic Felsic Intrusive Igneous Rock
Limestone
Calcium Carbonate (CaCO3)
Dumortierite Quartz
Al7BO3(SiO4)3O3 (Aluminum borate silicate)
Garnet Schist
Garnetiferous Micaceous Schist
Petrified Wood
Silicified Wood (SiO2)
Diamond
Diamond (Pure Carbon, C)
Schist
Chlorite/Mica Schist
Mica Schist
Mica Schist (predominantly Muscovite/Biotite)
Schist
Mica Schist
Mica Schist
Muscovite/Biotite Schist
Mica Schist with Pyrite
Muscovite/Biotite Schist with Iron Sulfide (FeS2)
Graphite-veined Quartzite
Meta-sedimentary Quartzite with Carbonaceous/Graphitic Inclusions (SiO2 + C)
Mookaite Jasper
Siliceous (chert) sedimentary rock, a form of Jasper
Jasper (Zebra Jasper)
Silicon Dioxide (SiO2) with impurities
Red Jasper (Brecciated or Mottled)
Silicon Dioxide (SiO2) with iron oxide inclusions
Gneiss
Gneiss (pronounced 'nice')
N/A - Image does not contain a rock or mineral
Anthropogenic textile material
Quartz Pebble
Silicon Dioxide (SiO2)
Mica Schist
Mica Schist (primarily Muscovite or Biotite sheet silicates)
Gneiss
Gneiss
Pink Granite
Phaneritic intrusive igneous rock (Felsic)
Banded Gneiss
Gneiss (Metamorphic high-grade, predominantly SiO2, Al2O3, K2O, Na2O)
Basalt (River Pebble)
Basalt (extrusive mafic rock)
Banded Agate (specifically Botswana Agate or Water-line Agate)
Chalcedony (cryptocrystalline variety of Quartz), SiO2
Carnelian
Carnelian Chalcedony (SiO2 with Iron Oxide impurities)
Granodiorite
Granodiorite (Intermediate to Felsic Intrusive Rock)
Feldspar (specifically Orthoclase)
Potassium Aluminum Silicate (KAlSi3O8)
Mica Schist
Mica Schist (primarily Muscovite and Quartz)
Prehnite
Prehnite - Ca2Al(AlSi3O10)(OH)2
Carnelian Agate
Silicon Dioxide (SiO2) - Variety: Chalcedony
Sandstone
Arenite (composed primarily of SiO2)
Slate
Foliated Metamorphic Rock (primarily clay minerals and micas)
Green Quartz (Aventurine)
Silicon Dioxide with Fuchsite inclusions (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)
Metaconglomerate
Metaconglomerate (Quartzite conglomerate)
Nuummite
Nuummite (Orthoamphibole rock / Anthophyllite-Gedrite blend)
Tumbled Moonstone
Feldspar (Orthoclase/Albite), KAlSi3O8
Basalt River Stone
Basalt (Mafic volcanic rock, primarily Plagioclase and Pyroxene)
Sandstone (Stream-rounded Cobble)
Arenite (composed primarily of SiO2, Silica)
Schist (Biotite/Mica Schist)
Medium-grade regional metamorphic rock (rich in Phyllosilicates)
Quartzite River Rock (with Limonite staining)
Quartzite (SiO2)
Oolitic Chert
Silicon Dioxide (SiO2) with oolitic texture