Sandstone (Ferruginous)
Arenite with Iron-Oxide Cement
sedimentary
Category
Metamorphic (Likely Gneiss Or Schist Based On Texture)
Browse metamorphic (likely gneiss or schist based on texture) specimens identified by the Rock Identifier community.
Basalt
Basalt (Mafic Extrusive)
igneous
Agate (specifically Carnelian Agate or Lake Superior style Agate)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
mineral
Petrified Wood
Silicified wood (Quartz, Chalcedony, or Opal)
sedimentary
Slate
Foliated Metamorphic Rock (Mainly composed of Quartz, Illite, Chlorite)
metamorphic
Chert (or Flint)
Chert (Sedimentary Cryptocrystalline Sio2)
sedimentary
Quartzite (River Pebble)
Quartzite (SiO2)
metamorphic
Red Quartzite Slipper Stone
Quartzite (SiO2)
metamorphic
Quartzite
Quartzite (SiO2)
metamorphic
Basalt with Iron Oxidation
Vesicular Basalt (Aphanitic Mafic Igneous Rock)
igneous
Smoky Quartz
Quartz (SiO₂)
Mineral
Sandstone (likely Quartzose Sandstone)
Arenite (SiO2 predominantly)
sedimentary
Lepidolite in Quartz (Obelisk)
K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2 (Lepidolite)
metamorphic
Quartzite (River Pebble)
Metamorphic Quartz (SiO2)
metamorphic
Chalcedony Nodule (Commonly known as Agate or Chert)
Microcrystalline Quartz (SiO2)
mineral
Slag (Industrial Byproduct)
Artificial silicate/iron byproduct
Mineral description (Anthropogenic material)
Emerald
Beryl (Be3Al2(SiO3)6) with Chromium/Vanadium impurities
mineral
Yellow Quartzite River Stone
Quartzite (primarily SiO2)
metamorphic
Botryoidal Black Chalcedony Geode (Black Grape Agate)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Mineral
Stichtite in Serpentine (Atlantasite)
Mg6Cr2CO3(OH)16·4H2O in Mg3Si2O5(OH)4
metamorphic
Basalt
Basalt (Mafic igneous rock)
igneous
Quartzite pebble
Quartzite (SiO2)
metamorphic
River Cobbles (Basalt, Quartzite, and Sandstone mix)
Fluvial detritus (primarily SiO2, Plagioclase, and Pyroxene mix)
Mixed: Igneous and Sedimentary
Fossilized Bone Fragment
Permineralized Skeletal Element (Likely Vertebrate)
sedimentary
Epidote
Epidote (formula: Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))
mineral
Sandstone (Micaceous/Feldspathic variant)
Arenite (specifically subarkose or lithic arenite)
sedimentary
Milky Quartz Cobble
Silicon Dioxide (SiO2)
mineral
Sandstone (likely Arkosic or Quartzose)
Sandstone (SiO2 dominated)
sedimentary
Epidosite (Epidote-rich rock)
Epidosite (consisting primarily of Epidote: {Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH))
metamorphic
Tektite (likely Australite)
Tektite (no specific chemical formula as it's a natural glass of variable composition, mostly SiO2, Al2O3, FeO, MgO, CaO, K2O, Na2O, TiO2)
Mineral (specifically a mineraloid)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Iron Oxide staining)
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Quartz with Muscovite Mica
Silicon Dioxide (SiO2) with Potassium Aluminum Silicate Hydroxide Fluoride (KAl2(AlSi3O10)(F,OH)2)
mineral
Greenschist
Greenschist (composed primarily of Chlorite, Actinolite, and Epidote)
metamorphic
Siltstone with Quartz Vein
Siltstone (primarily SiO2, Al2O3, Fe2O3)
sedimentary
Basalt with Iron Oxides
Mafic Igneous Rock (Mafite)
igneous
Pink Anthracite Coal (dyed)
Anthracite Coal (Artificially Colored)
Sedimentary Rock (Altered)
Sandstone
Sandstone (clastic sedimentary rock, composed predominantly of sand-sized minerals or rock fragments)
Sedimentary Rock
Basalt
Basalt (Mafic Extrusive Igneous Rock)
igneous
Quartzite
Metamorphosed Quartz Sandstone (SiO2)
metamorphic
Quartzite
Quartzite (primarily SiO2)
metamorphic
Pink Granite
Phaneritic Felsic Igneous Rock (Rich in K-Feldspar)
igneous