Amethyst Geode/Cluster
Quartz (SiO2) - variety Amethyst
Mineral
Category
Anthropogenic (Man Made Material Processed By Nature)
Browse anthropogenic (man made material processed by nature) specimens identified by the Rock Identifier community.
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Jade
Jadeite or Nephrite
Mineral/Mineraloid
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Quartz (Water-worn pebble)
Silicon Dioxide (SiO2)
mineral
Fluorite (likely)
Calcium Fluoride (CaF2)
Mineral
Quartz
Quartz (SiO₂ - Silicon Dioxide)
mineral
Quartz with Iron Stains
Quartz (SiO2) with iron oxide/hydroxide staining
Mineral
Quartz (variety of colors)
SiO2 (Silicon Dioxide)
Mineral
Quartz Geode (likely within Limestone or Dolomite matrix)
Quartz (SiO₂)
Mineral within a Sedimentary Rock
Quartz
Quartz (Silicon Dioxide - SiO2)
Mineral
Geode (unopened)
Chert / Chalcedony Geode (SiO2)
sedimentary
Conglomerate
Sedimentary Conglomerate
sedimentary
Picture Jasper
Silicon Dioxide (SiO2) - Opaque Chert/Quartzite variety
sedimentary
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
Yellow Quartz Pebble
Silicon Dioxide (SiO2)
mineral
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
Marble
Metamorphosed Limestone/Dolomite
metamorphic
River Pebble (likely Quartzite or Basalt)
Quartzite (SiO2 as primary mineral)
metamorphic
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
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
Conglomerate
Conglomerate (Detrital sedimentary rock)
sedimentary
Basalt
Basalt (dominated by plagioclase feldspar and pyroxene)
igneous
Greisen
Greisen
Metamorphic
Pumice
Pumice (volcanic rock)
Igneous
Dyed Quartz Crystals
Silicon Dioxide (SiO2) with artificial pigment
mineral
Dyed Fuchsia Tiger’s Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
metamorphic
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)
Sodalite beads
Sodalite, Na₈(Al₆Si₆O₂₄)Cl₂, likely with minor lazurite/pyrite or calcite inclusions
mineral
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
Tumbled goldstone-like quartz pebble
Likely iron-stained quartz or jasper; exact identification requires testing
mineral
Goldstone (aventurine glass)
Synthetic copper-bearing soda-lime glass; commonly sold as red goldstone
gemstone
Basalt River Pebble
Aphanitic Mafic Igneous Rock
igneous
Gold (10K Alloy)
Aurum (Au) with alloying metals (Cu, Ag, Zn)
mineral
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Yellow Quartz / Citrine Quartz
Silicon Dioxide (SiO2)
mineral
Basalt
Basalt
igneous
Granite
Granite (plutonic igneous rock)
igneous
Weathered Sandstone
Quartz Arenite / Clastic Sedimentary Rock
sedimentary