Asphalt (Bituminous Concrete)
Asphaltum / Bitumen-Aggregate Matrix
Technonatural composite (often containing sedimentary/igneous aggregate)
Category
Antropogenic (Man Made Glass Byproduct)
Browse antropogenic (man made glass byproduct) specimens identified by the Rock Identifier community.
Learn about Antropogenic (Man Made Glass Byproduct) in the encyclopedia
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Red Sandstone
Arenite (Ferruginous Sandstone)
sedimentary
Pink calcite (likely)
Calcite — calcium carbonate, CaCO₃
mineral
Jasper
Silicon dioxide (SiO2) with impurities
sedimentary
Dark rounded pebble, likely basalt or slag
Probable fine-grained mafic rock; possibly basalt (plagioclase–pyroxene) or industrial iron/steel slag
igneous
Diabase (Greenstone)
Diabase (Dolerite)
igneous
Quartz (Druzy / Goldstone Gemstone Cabochon)
Silicon Dioxide (SiO2)
gemstone
Blue glass-like gemstone specimen (likely dyed or synthetic quartz)
Uncertain; possibly blue-dyed quartz or synthetic glass, not confidently identifiable from the image
gemstone
Tumbled pale quartz (likely milky quartz)
Quartz, silicon dioxide (SiO₂)
mineral
Iron Slag
Anthropogenic Ferro-silicate
mineral
Ferruginous Sandstone (Ironstone)
Clastic Sedimentary Rock (composed of SiO2 with Fe2O3/FeO(OH) cement)
sedimentary
Limestone
Calcareous sedimentary rock (CaCO3)
sedimentary
Green Fluorite
Calcium Fluoride (CaF2)
mineral
Red Sandstone
Arenite (with Iron Oxide / Hematite staining)
sedimentary
Chert (specifically Flint Arrowhead)
Silicon dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Dark gray rounded stone, possibly basalt or slag
Uncertain; likely fine-grained basalt (plagioclase–pyroxene) or iron-rich industrial slag
igneous
Scoria
Scoriaceous Basalt
igneous
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Dyed Blue Agate Slice
Silicon Dioxide (SiO2)
mineral
Granite
Granite (felsic intrusive igneous rock)
igneous
Weathered pegmatite or feldspar-rich granite fragment
Granitic pegmatite, composed mainly of potassium feldspar and quartz, with minor mica; exact identification is uncertain from the photograph
igneous
Rose Quartz (likely carved)
Rose Quartz (SiO2)
Mineral
Quartz with Host Rock
Silicon Dioxide (SiO2)
mineral
Bog Iron / Limonite Concretion
Goethite/Limonite mixture (FeO(OH)·nH2O)
sedimentary
Banded Calcite or Travertine
Calcium Carbonate (CaCO3)
Sedimentary
Quartzite
Quartzite (primarily SiO2)
metamorphic
Obsidian
Volcanic glass (SiO2 - Silicon Dioxide with impurities)
igneous
Sandstone with Iron Staining
Arenite (SiO2 with Fe2O3)
sedimentary
Quartz
Silicon Dioxide (SiO2)
mineral
Tumbled chalcedony (likely blue-gray agate)
Cryptocrystalline quartz, SiO₂; chalcedony/agate variety
mineral
Coral Rock (Coquina)
Biogenic Limestone (Calcium Carbonate - CaCO3)
sedimentary
Quartz pebble
Quartz (Silicon dioxide, SiO2)
mineral
Colorless faceted gemstone (likely cubic zirconia)
Cubic zirconia, zirconium dioxide (ZrO₂); possibly synthetic quartz or glass imitation
gemstone
Quartz
Silicon Dioxide (SiO2)
mineral
Quartz (Milky/Common)
Silicon Dioxide (SiO2)
mineral
Quartz crystal
Quartz (Silicon dioxide, SiO2)
mineral
Sodalite beads
Sodalite, Na₈(Al₆Si₆O₂₄)Cl₂, likely with minor lazurite/pyrite or calcite inclusions
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Obsidian
Obsidian (Volcanic Glass)
igneous
Granite
Granite (a common rock type, not a single mineral with a formula. Composed primarily of quartz, feldspar, and mica/amphibole).
igneous
Polished/tumbled brown jasper or iron-rich chert
Microcrystalline quartz (SiO₂), commonly colored by hematite/goethite
mineral
Limestone
Calcium Carbonate (CaCO3)
sedimentary