Anthropogenic (Man Made Material Processed By Nature)

Browse anthropogenic (man made material processed by nature) specimens identified by the Rock Identifier community.

Serpentinite

Serpentinite (Mg, Fe, Ni)₃Si₂O―(OH)₄

metamorphic

Diamond

Diamond (C)

Mineral

Diamond

Diamond (C)

Mineral

Pink Granite

Felsic Plutonic Rock (primarily Quartz, Potassium Feldspar, and Plagioclase)

igneous

Sandstone (Quartzose Sandstone)

Clastic Sedimentary Rock (primarily SiO2)

sedimentary

Green Aventurine (Green Quartzite)

Silicon Dioxide (SiO2) with inclusions of Fuchsite (chromium-rich mica)

metamorphic

Ferruginous Quartz (Iron-stained Quartz)

Silicon Dioxide (SiO2) with Hematite/Limonite impurities

mineral

Petrified Wood (Silicified Wood)

Silicified Wood (primarily Chalcedony/Quartz, SiO2)

mineral

Diamond

Diamond (C)

Mineral

Greenschist

Greenschist facies rock

Metamorphic

Stainless Steel Spoon

Iron-Chromium Alloy (Fe + Cr + Ni)

mineral-based human-made alloy

Pebble (likely Quartzite or Chert)

Clastic Sediment, potentially composed of SiO₂ (Quartz)

Mineral, Sediment

Laterite (iron-rich nodule, possibly Bauxite as a subtype)

Laterite (composed of various minerals including goethite, hematite, gibbsite, etc.)

Sedimentary

Biotite Schist (likely)

Biotite Schist (rock), Biotite (mineral)

Metamorphic

Quartz (likely macrocrystalline variety)

Quartz (SiO₂)

Mineral

Conglomerate

Conglomerate (a clastic sedimentary rock)

Sedimentary

Jasper Breccia

Brecciated Jasper (Silicon Dioxide with Iron Oxide inclusions, SiO2)

sedimentary

Basalt (River Stone)

Aphanitic Mafic Igneous Rock

igneous

Lapis Lazuli

A metamorphic rock primarily composed of lazurite (Na,Ca)8[(S,SO4,Cl)2|(Al6Si6O24)], calcite (CaCO3), and pyrite (FeS2).

Mineral

Calcite

Calcite (CaCO3)

Mineral

Sandstone

Arenite (general term for sandstone)

Sedimentary Rock

Jasper

Silicon Dioxide (SiO2) - a variety of Chalcedony (Cryptocrystalline Quartz)

Mineral

Milky Quartz

Quartz (SiO₂)

Mineral

Red Jasper (Opaque Chalcedony)

Silicon Dioxide (SiO2) with Hematite (Fe2O3) inclusions

mineral

Muscovite Mica

Muscovite (KAl₂(AlSi₃O₁₀)(F,OH)₂))

Mineral

Quartz

Quartz (SiO₂)

Mineral

Clear Quartz (or Rock Crystal)

Quartz (SiO₂ - Silicon Dioxide)

Mineral

Orange Calcite (likely polished specimen)

Calcite

Mineral

Oak-grain Laminate (Industrial/Decorative Furniture Finish)

Melamine Resin-impregnated Decorative Paper on Particleboard (Cellulose/Thermosetting Plastic)

not a rock (synthetic material)

Chrysoprase

Chalcedony (cryptocrystalline quartz) with nickel inclusions; SiO2

Mineral

Quartz (likely) / Siliceous rock with quartz phenocrysts (if a rock fragment)

Quartz (SiO₂)

Mineral

Cat's Eye Moonstone (Simulated/Synthetic or natural Cat's Eye Quartz/Glass)

There is no single scientific name. The appearance suggests either: Moonstone (feldspar group), Cat's Eye Quartz (SiO2), Apatite (Ca5(PO4)3(F,Cl,OH)), or most likely a synthetic material such as Fiber Optic Glass or 'Opalite' (a type of glass).

Mineral

Bloodstone / Heliotrope

Silicon dioxide (SiO2) with inclusions

Mineral (variety of Chalcedony)

Fossiliferous Rock (likely Dinosaur Fossil in Matrix)

Permineralized Vertebrate Fossil (Calcium Carbonate/Silica replaced bone material)

sedimentary

River Rock

Sedimentary Rock (various compositions)

sedimentary

Quartz (likely a weathered/tumbled piece)

Quartz (SiO₂)

Mineral

Quartzite

Quartzite (Primary mineral: Quartz, SiO2)

metamorphic

Granite

Granite (a common rock type, not a single mineral; composed primarily of Quartz, Feldspar (Orthoclase and Plagioclase), and Mica (Biotite and/or Muscovite) and/or Amphibole)

Igneous