Rutilated Quartz
SiO2 (Quartz) with TiO2 (Rutile inclusions)
Mineral
Category
Anthropogenic (Man Made Material Processed By Nature)
Browse anthropogenic (man made material processed by nature) specimens identified by the Rock Identifier community.
Quartz
Quartz (SiO₂ - Silicon Dioxide)
mineral
Quartz (variety of colors)
SiO2 (Silicon Dioxide)
Mineral
Granite
Granite (a felsic intrusive igneous rock)
Igneous Rock
Chalcedony (Banded/Mottled Variety)
Chalcedony (a cryptocrystalline variety of Quartz, SiO2)
Mineral
Granite (likely a river or beach pebble)
Granite (a felsic intrusive igneous rock primarily composed of quartz, feldspar, and mica)
Igneous
Conglomerate
Conglomerate (Clastic sedimentary rock)
sedimentary
Fluorite (likely)
Calcium Fluoride (CaF2)
Mineral
Granite
Granite (a plutonic igneous rock)
Igneous
Talc
Talc (Mg₃Si₄O₁₀(OH)₂)
Mineral
Quartz with Iron Stains
Quartz (SiO2) with iron oxide/hydroxide staining
Mineral
Ferruginous Quartz
Quartz (Silicon Dioxide) with Iron Inclusion, SiO2
mineral
Quartz
Quartz (Silicon Dioxide - SiO2)
Mineral
Quartz Geode (likely within Limestone or Dolomite matrix)
Quartz (SiO₂)
Mineral within a Sedimentary Rock
Geode (unopened)
Chert / Chalcedony Geode (SiO2)
sedimentary
Yellow Jade (often Serpentine or Dolomite)
Primarily Serpentine (Mg3Si2O5(OH)4) or Dolomite (CaMg(CO3)2), though the term 'yellow jade' is also sometimes applied to varieties of true nephrite or jadeite.
Mineral, often a rock given its aggregate nature
Quartz
Quartz (SiO2 - Silicon Dioxide)
Mineral, often found as detrital grains in sedimentary rocks
Dark-colored Igneous Rock (likely Basalt or Diabase)
Basalt (extrusive igneous) or Diabase (intrusive igneous)
Igneous Rock
Quartz (Druzy) in host rock
SiO₂ (Silicon Dioxide) as Quartz, with unspecified host rock components (likely silicates and iron oxides)
Mineral
Granite (tumbled pebble)
Granite (Plutonic Igneous Rock)
Igneous Rock
Marble
Metamorphosed Limestone/Dolomite
metamorphic
Conglomerate
Conglomerate (Detrital sedimentary rock)
sedimentary
Picture Jasper
Silicon Dioxide (SiO2) - Opaque Chert/Quartzite variety
sedimentary
Shale or Slate with Quartz Veins
Shale (fine-grained clastic sedimentary rock) or Slate (low-grade metamorphic rock formed from shale) with Quartz (SiO2) veins
Metamorphic, likely Sedimentary with Quartz veins
Basalt
Basalt (dominated by plagioclase feldspar and pyroxene)
igneous
Greisen
Greisen
Metamorphic
Pumice
Pumice (volcanic rock)
Igneous
Iron Ore / Ironstone Concretion
Mixture of iron oxide/hydroxide minerals, likely some combination of Hematite (Fe2O3), Goethite (α-FeOOH), and Limonite (a general term for hydrated iron oxides of variable composition) or potentially Bauxite (a mixture of aluminum hydroxides, often with iron oxides, (Al(OH)3) and FeO(OH)). The visual characteristics strongly suggest iron-rich material.
Mineral, specifically an iron ore
Chert or Flint (polished/water-worn)
Chert (a microcrystalline or cryptocrystalline variety of quartz, SiO2). Flint is a specific variety of chert.
Sedimentary (most likely, as Chert is a sedimentary rock often found as nodules in limestone or as bedded deposits; however, it can also form by metasomatic replacement, which leans towards metamorphic processes under certain conditions)
Carnelian (Red Agate/Chalcedony)
Cryptocrystalline Quartz (SiO2) with Hematite impurities
mineral
Mixed Quartz and River Pebbles (Stone Collection)
Mixed assortment containing mainly Silicon Dioxide (SiO2)
igneous, sedimentary, metamorphic, and mineral
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Gold (10K Alloy)
Aurum (Au) with alloying metals (Cu, Ag, Zn)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
mineral
Citrine or Yellow Quartz
Silicon Dioxide (SiO2) with iron impurities
mineral
Diamond (Princess Cut Gemstone)
Carbon (C)
mineral
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Sandstone
Arenite (composed primarily of Quartz: SiO2)
sedimentary
Diamond (Princess Cut)
Carbon (C)
mineral
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Rhodonite
Rhodonite (MnSiO3)
mineral