Ironstone Concretion (Limonite/Hematite Nodules)
Ironstone (principally Limonite FeO(OH)·nH2O or Hematite Fe2O3 mixed with silica/clay)
sedimentary
Category
Mineral (Evaporite)
Browse mineral (evaporite) specimens identified by the Rock Identifier community.
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Ferruginous Sandstone (Red Sandstone)
Arenite with Hematite/Limonite cement
sedimentary
Banded Sandstone (Quartzite-rich)
Clastic Sedimentary Rock (SiO2 with Iron Oxide impurities)
sedimentary
Ferruginous Quartz (Iron-stained Quartz)
Silicon Dioxide (SiO2) with Hematite/Goethite inclusions
mineral
Red Sandstone
Arenite (Ferruginous Sandstone)
sedimentary
Gneiss
Foliated Metamorphic Rock
metamorphic
Quartz (Smoky/Milky)
Silicon Dioxide (SiO2)
mineral
Granite
Granitoid (dominated by Quartz and Feldspar)
igneous
Sedimentary Outcrop (Sandstone/Shale)
Sedimentary bedrock formation (variable composition)
sedimentary
Gneiss (Granitic Gneiss)
Gneiss
metamorphic
Metal Alloy (Jewelry)
Not a naturally occurring rock or mineral; likely a metal alloy for jewelry. Possible compositions include sterling silver (92.5% silver, 7.5% copper), or other silver/gold alloys.
Man-made Material (jewelry, metal alloy)
Mixed Chalcedony and Jasper Bracelet (possibly 'Ocean Jasper' or similar banded variety for brown beads, and blue/grey Chalcedony for the translucent beads)
Chalcedony (SiO2), Jasper (SiO2 with impurities)
Mineral (specifically a cryptocrystalline variety of Quartz)
Basalt with Quartz/Calcite matrix
Basalt (SiO2 with Ca/Mg/Fe silicates) on a Mineral Matrix
igneous
Granite
Phaneritic Felsic Igneous Rock (Granite)
igneous
Basalt
Mafic Igneous Rock (composed primarily of Pyroxene and Plagioclase Feldspar)
igneous
Granite
Granite
igneous
Quartzite
Quartzite (SiO2)
metamorphic
Slag (Industrial Glass Slag)
Amorphous Silicate Glass (often containing Al, Ca, Mg, and Ti oxides)
Mineraloid (Industrial byproduct)
Chalk
Calcium Carbonate (CaCO3)
sedimentary
Vesicular Basalt
Vesicular Basalt
igneous
Basalt (Vesicular)
Basalt (Mafic Extrusive Igneous Rock)
igneous
Quartz / Quartzite
Silicon Dioxide (SiO2)
metamorphic
Glaucophane Schist (Blueschist)
Blueschist (Glaucophane-bearing schist)
metamorphic
Granite
Phaneritic Felsic Igneous Rock
igneous
Basalt
Extrusive mafic igneous rock
igneous
Quartz (River Pebble)
Silicon Dioxide (SiO2)
mineral
Limonite and Goethite (Ironstone)
Hydrous Iron Oxide Mixture (FeO(OH)·nH2O)
sedimentary
Ferruginous Quartz (Iron-stained Quartz)
Silicon Dioxide (SiO2) with Hematite/Limonite impurities
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Turquoise
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
mineral
Limonite (Iron Stone/Ocher)
Limonite (FeO(OH)·nH2O)
mineral
Prehnite
Ca2Al(AlSi3O10)(OH)2 (Calcium Aluminum Silicate hydroxide)
mineral
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Arsenopyrite with Quartz
Arsenopyrite (FeAsS)
mineral
Yellow Ocher (Limonite)
Limonite (Hydrated Iron Oxide) - FeO(OH)·nH2O
mineral
Chalcopyrite in Quartz (Gold Ore Matrix)
CuFeS2 (Chalcopyrite) with SiO2 (Quartz)
mineral
Undetermined Due to Blur (Possible Flesh-Tone Mineral)
Unknown (Insufficient Visual Clarity)
Mineral
Conglomerate
Clastic Sedimentary Conglomerate (SiO2 primarily)
sedimentary
Granite or Granitic Gneiss River Rock
Granite / Gneiss
Igneous or Metamorphic
Limonite (Iron Ore/Hydrated Iron Oxide)
Limonite (mixture of FeO(OH)·nH₂O minerals, mainly Goethite, FeO(OH) and Lepidocrocite, FeO(OH))
Mineral