Rock Identifier

Category

Mineraloid (Human Made Geological Specimen)

Browse mineraloid (human made geological specimen) specimens identified by the Rock Identifier community.

Rock Specimen (Unclassified rock specimen) — sedimentary

Rock Specimen

Unclassified rock specimen

Blue Obsidian (Volcanic Glass (SiO2 with inclusions)) — igneous

Blue Obsidian

Volcanic Glass (SiO2 with inclusions)

Artificial Rock Face (Faux Rock) (Glass Fiber Reinforced Concrete (GFRC)) — man-made/construction material

Artificial Rock Face (Faux Rock)

Glass Fiber Reinforced Concrete (GFRC)

man-made/construction material

Chalcedony (Agate / Jasper Specimen) (Silicon Dioxide (SiO2)) — mineral

Chalcedony (Agate / Jasper Specimen)

Silicon Dioxide (SiO2)

Chert (and Flint) (Silicon Dioxide (SiO2)) — sedimentary

Chert (and Flint)

Silicon Dioxide (SiO2)

Small polished brown stone (Indeterminate; possibly tumbled jasper, brown agate, or another iron-stained silicate) — mineral

Small polished brown stone

Indeterminate; possibly tumbled jasper, brown agate, or another iron-stained silicate

Chalk (Calcite (CaCO3)) — sedimentary

Chalk

Calcite (CaCO3)

Tumbled feldspar-rich stone, likely granite or granitic pegmatite (Quartz–feldspar aggregate; likely alkali feldspar and plagioclase with minor quartz, possibly altered) — igneous

Tumbled feldspar-rich stone, likely granite or granitic pegmatite

Quartz–feldspar aggregate; likely alkali feldspar and plagioclase with minor quartz, possibly altered

Sandstone (Arenite) — sedimentary

Sandstone

Arenite

Colorless faceted gemstone (likely cubic zirconia) (Cubic zirconia, ZrO₂ (synthetic zirconium dioxide); possibly synthetic glass or lab-grown diamond) — gemstone

Colorless faceted gemstone (likely cubic zirconia)

Cubic zirconia, ZrO₂ (synthetic zirconium dioxide); possibly synthetic glass or lab-grown diamond

Chert / Flint Nodule (Microcrystalline Quartz (SiO2)) — sedimentary

Chert / Flint Nodule

Microcrystalline Quartz (SiO2)

Chert (Nodule) (Chert (Cryptocrystalline Silica, SiO2)) — sedimentary

Chert (Nodule)

Chert (Cryptocrystalline Silica, SiO2)

Chert (Flint) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Flint)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Crinoid Columnal Fossil in Chert (Crinoidea stemming section in Microcrystalline Quartz (SiO2)) — fossil

Crinoid Columnal Fossil in Chert

Crinoidea stemming section in Microcrystalline Quartz (SiO2)

Concretion (Sedimentary Concretion (Ironstone / Calcite Concretion)) — sedimentary

Concretion

Sedimentary Concretion (Ironstone / Calcite Concretion)

Banded Agate (specifically Carnelian Agate slice) (Chalcedony (cryptocrystalline variety of Quartz), SiO2) — mineral

Banded Agate (specifically Carnelian Agate slice)

Chalcedony (cryptocrystalline variety of Quartz), SiO2

Mixed Rock and Mineral Collection (Various geological specimens) — igneous, sedimentary, and metamorphic

Mixed Rock and Mineral Collection

Various geological specimens

igneous, sedimentary, and metamorphic

Rounded brown-gray stone, possibly weathered conglomerate or sandstone (Indeterminate clastic sedimentary rock; likely poorly cemented sandstone/conglomerate) — sedimentary

Rounded brown-gray stone, possibly weathered conglomerate or sandstone

Indeterminate clastic sedimentary rock; likely poorly cemented sandstone/conglomerate

Chert / Flint (Microcrystalline Quartz (SiO2)) — sedimentary

Chert / Flint

Microcrystalline Quartz (SiO2)

Granite (Phaneritic Felsic Igneous Rock) — igneous

Granite

Phaneritic Felsic Igneous Rock

Bituminous Coal (with Anthracite or Vitrinite inclusion) (Organic-rich Sedimentary Rock (Carboniferous classification)) — sedimentary

Bituminous Coal (with Anthracite or Vitrinite inclusion)

Organic-rich Sedimentary Rock (Carboniferous classification)

Polished limestone or marble slab (Calcite-rich carbonate rock; likely marble (CaCO₃)) — metamorphic

Polished limestone or marble slab

Calcite-rich carbonate rock; likely marble (CaCO₃)

Iron-stained quartz-rich rock, possibly jasper or chert (Microcrystalline quartz (SiO₂) with iron oxides/hydroxides) — mineral

Iron-stained quartz-rich rock, possibly jasper or chert

Microcrystalline quartz (SiO₂) with iron oxides/hydroxides

Tumbled dark green stone, likely serpentine or greenstone (Serpentinite (hydrated magnesium silicate minerals, chiefly antigorite/lizardite); possible chlorite-rich greenstone) — metamorphic

Tumbled dark green stone, likely serpentine or greenstone

Serpentinite (hydrated magnesium silicate minerals, chiefly antigorite/lizardite); possible chlorite-rich greenstone

Rainbow Hematite (Titanium Coated) (Iron(III) oxide (Fe2O3) with Titanium/Metal Oxide coating) — mineral

Rainbow Hematite (Titanium Coated)

Iron(III) oxide (Fe2O3) with Titanium/Metal Oxide coating

Chert (Flint) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Flint)

Silicon Dioxide (SiO2)

Obsidian (Volcanic Glass (Amorphous silicon dioxide with trace impurities)) — igneous

Obsidian

Volcanic Glass (Amorphous silicon dioxide with trace impurities)

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

Blue glass-like gemstone specimen (likely dyed or synthetic quartz)

Uncertain; possibly blue-dyed quartz or synthetic glass, not confidently identifiable from the image

Granite (Phaneritic Igneous Rock (composed primarily of Quartz, Alkali Feldspar, and Plagioclase)) — igneous

Granite

Phaneritic Igneous Rock (composed primarily of Quartz, Alkali Feldspar, and Plagioclase)

Fossilized Oyster in Flint (Gryphaea or Exogyra embedded in SiO2 (Flint/Chert)) — fossil

Fossilized Oyster in Flint

Gryphaea or Exogyra embedded in SiO2 (Flint/Chert)

Fossil gastropod shell (Fossilized marine gastropod; exact genus/species requires locality and examination) — fossil

Fossil gastropod shell

Fossilized marine gastropod; exact genus/species requires locality and examination

Polished orbicular granite (likely K2-type granite) (Granite, chiefly quartz, alkali feldspar, plagioclase, and dark amphibole/biotite; possible epidote-rich orbicules) — igneous

Polished orbicular granite (likely K2-type granite)

Granite, chiefly quartz, alkali feldspar, plagioclase, and dark amphibole/biotite; possible epidote-rich orbicules

Vesicular Basalt (or Scoria) (Vesicular Basalt) — igneous

Vesicular Basalt (or Scoria)

Vesicular Basalt

Black Obsidian (Volcanic Glass (Amorphous SiO2 with trace impurities)) — igneous

Black Obsidian

Volcanic Glass (Amorphous SiO2 with trace impurities)

Chert (Polished River Pebble) (Chert (SiO2)) — sedimentary

Chert (Polished River Pebble)

Chert (SiO2)

Limestone Pebble (Sedimentary Calcium Carbonate (CaCO3)) — sedimentary

Limestone Pebble

Sedimentary Calcium Carbonate (CaCO3)

Blue Agate (Dyed) (Silicon Dioxide (Chalcedony), SiO2) — gemstone

Blue Agate (Dyed)

Silicon Dioxide (Chalcedony), SiO2

Crushed Stone (Likely Limestone or Granite) (Calcium Carbonate (CaCO3) for Limestone / Quartz and Feldspar for Granite) — sedimentary or igneous

Crushed Stone (Likely Limestone or Granite)

Calcium Carbonate (CaCO3) for Limestone / Quartz and Feldspar for Granite

sedimentary or igneous

Cherry Quartz with Rose Quartz (Crystalline Quartz (SiO2) with glass-based synthetic components) — gemstone

Cherry Quartz with Rose Quartz

Crystalline Quartz (SiO2) with glass-based synthetic components

Megalodon Shark Tooth (Otodus megalodon) — fossil

Megalodon Shark Tooth

Otodus megalodon

Opalite (Synthetic Opalite (Man-made glass)) — mineral

Opalite

Synthetic Opalite (Man-made glass)

Titanium Amethyst Geode (Silicon Dioxide (SiO2) with Titanium/Metal Vapor Deposition Layer) — mineral

Titanium Amethyst Geode

Silicon Dioxide (SiO2) with Titanium/Metal Vapor Deposition Layer