Anthropogenic (Man Made Material Mimicking Sedimentary Rock)

Browse anthropogenic (man made material mimicking sedimentary rock) specimens identified by the Rock Identifier community.

Quartzite

Quartzite (primarily SiO2)

metamorphic

Quartz (possibly milky quartz)

Quartz (Silica; SiO₂)

Mineral

Labradorite

Labradorite ((Ca, Na)(Al, Si)4O8)

mineral

Quartz with Iron Stains

Quartz (SiO2) with iron oxide/hydroxide staining

Mineral

Quartz

Quartz (SiO₂)

Mineral

Diamond (or Cubic Zirconia)

Carbon (C) or Zirconium Dioxide (ZrO2)

mineral

Metallic Ornament / Jewelry

N/A - This is an artificial object, not a geological specimen.

This appears to be a man-made metallic object, likely jewelry, not a natural rock, mineral, or geological specimen.

Biotite Mica

Biotite (K(Mg,Fe)3AlSi3O10(F,OH)2)

mineral

Quartz

Silicon Dioxide (SiO2)

Mineral

Coal (most likely Bituminous or Anthracite)

Bituminous Coal (Grade of Coal), Anthracite (Grade of Coal)

Sedimentary Rock

Aquamarine and clear quartz

Aquamarine (Be3Al2Si6O18), Quartz (SiO2)

Mineral

Pumice

Pumice (volcanic rock)

Igneous

Quartzite

Quartzite (SiO2)

Metamorphic

Marble

Marbles are primarily composed of calcite (calcium carbonate, CaCO3) or dolomite (calcium magnesium carbonate, CaMg(CO3)2).

Metamorphic Rock

Chert (Flint)

Chert (predominantly SiO₂ - silicon dioxide)

sedimentary

Clear Quartz (or Rock Crystal)

Quartz (SiO₂ - Silicon Dioxide)

Mineral

Chalk

Calcareous Ooze (composed primarily of coccoliths)

Sedimentary Rock

Quartz (pebble)

Quartz (SiO₂)

Mineral

Quartz (Milky Quartz)

Quartz (SiO2 - Silicon Dioxide)

Mineral

Caliche (also known as hardpan, calcrete, kankar)

Primarily composed of calcium carbonate (CaCO₃), often mixed with other minerals like quartz, clay minerals, and iron oxides.

Mineral

Calcite

Calcite (Calcium Carbonate, CaCO3)

mineral

Marble

Metamorphosed Limestone/Dolomite

metamorphic

Agate

Agate (a variety of Chalcedony, SiO2)

Mineral

Jasper

Silicon Dioxide (SiO2)

Mineral

Quartz (in matrix)

Quartz (SiO₂)

mineral

Halite

Halite (NaCl)

Mineral

Quartz

Quartz (SiO₂ - Silicon Dioxide)

Mineral

Opalite

Man-made synthetic glass with opalescent effects (SiO2 + metal oxides)

mineraloid

Quartz

Silicon Dioxide (SiO₂)

Mineral

Muscovite Mica

Muscovite (Potassium Mica) KAl2(AlSi3O10)(OH)2

Mineral

Turquoise

Turquoise (CuAl6(PO4)4(OH)8·4H2O)

mineral

Red Jasper (beads)

Silicon Dioxide (SiO2) with iron inclusions

Sedimentary Rock

Fuchsite Quartzite

Fuchsite-bearing Quartzite

Metamorphic

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)

Chalcedony or Chert/Jasper with secondary mineral staining

SiO2 (for chalcedony/quartz) with possible secondary copper minerals (e.g., CuSiO3·nH2O for chrysocolla, Cu2(CO3)(OH)2 for malachite) or iron oxides/hydroxides.

Mineral, potentially a rock with chalcedony/jasper.

Limestone

Calcium Carbonate (CaCO3)

sedimentary

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