Sandstone
Clastic sedimentary rock (Quartz arenite/Arkose)
sedimentary
Category
Anthropogenic Specimen (Man Made Material)
Browse anthropogenic specimen (man made material) specimens identified by the Rock Identifier community.
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White Marble
Recrystallized Calcite (CaCO3)
metamorphic
Native Silver
Silver (elemental Ag)
mineral
Unakite
Altered Granite (Epidotized Granite)
metamorphic
Chert (Yellow Jasper/Flint)
Chert (Microcrystalline Silicon Dioxide, SiO2)
sedimentary
Chert (Nodule)
Chert (Silicon Dioxide, SiO2)
sedimentary
Chert (specifically Jasper or Flint variety)
Cryptocrystalline Quartz (SiO2)
sedimentary
Pyrite
Iron Sulfide (FeS2)
mineral
Tektite
Impactite (Natural Silicate Glass)
meteorite
Diamond (in jewelry setting)
Adamantine Carbon (C)
mineral
Chert
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Jasper variety)
Silicon Dioxide (SiO2)
sedimentary
Blue Slag Glass
Amorphous Silica (Byproduct of smelting)
Antropogenic (Man-made)
Slate
Metamorphic pelitic rock
metamorphic
Sandstone
Arenite
sedimentary
Chert (Flinty variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Tumbled orbicular granite
Granite, predominantly potassium feldspar, plagioclase, quartz, and biotite/hornblende
igneous
Dark gray rounded stone, possibly basalt or slag
Uncertain; likely fine-grained basalt (plagioclase–pyroxene) or iron-rich industrial slag
igneous
Vesicular volcanic rock, likely weathered pumice or scoria
Pumice/scoria; predominantly volcanic glass and feldspar, with possible iron oxides
igneous
Chert (Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Coquina / Fossiliferous Limestone
Coquina (composed primarily of Calcium Carbonate / CaCO3)
sedimentary
Sandstone (with iron staining)
Quartz Arenite / Ferruginous Sandstone
sedimentary
Sandstone (likely Fossiliferous)
Arenite / Fossiliferous Sandstone (SiO2 composition)
sedimentary
White Marble
Recrystallized Calcite Rock (CaCO3)
metamorphic
Green Aventurine
Quartz (SiO2) with Fuchsite inclusions
Mineral
Tumbled yellow quartz (likely citrine or iron-stained quartz)
Quartz, SiO₂; yellow color from trace iron or irradiation/heat-related coloration
mineral
Chert (specifically Zebra Chert/Flint)
Silicon Dioxide (SiO2)
sedimentary
Sandstone
Sedimentary Rock (Quartz Sandstone)
sedimentary
Malachite
Malachite (Cu2CO3(OH)2)
mineral
Sandstone
Arenite
sedimentary
Chert (often called Flint)
Chert (Microcrystalline Quartz, SiO2)
sedimentary
Chalky limestone
Micritic calcite (CaCO₃), likely biogenic limestone/chalk
sedimentary
Jasper Marble
Silicon Dioxide (SiO2) with Impurities
sedimentary
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Fossil bivalve shell
Likely an extinct or modern-like ribbed cockle/scallop; exact genus requires locality and diagnostic hinge features
fossil
Diorite (River Pebble)
Intermediate plutonic igneous rock
igneous
Fossiliferous Limestone (Coquina)
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Chert (Field-collected Arrowhead-shaped Fragment)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Malaysian 50 Sen Coin
Coinage (specific alloy unknown without metallurgical analysis, but typically brass or bronze for this denomination and era)
Man-made object (coin)
Quartzite
Silica (SiO2) quartzite
metamorphic
Ferruginous Sandstone (Ironstone)
Clastic Sedimentary Rock (composed of SiO2 with Fe2O3/FeO(OH) cement)
sedimentary