Rock Identifier

Category

Man Made Object (Coin)

Browse man made object (coin) specimens identified by the Rock Identifier community.

Petrified Wood (Silicified Wood (primarily SiO2)) — sedimentary

Petrified Wood

Silicified Wood (primarily SiO2)

Hematite (Hematite (Fe2O3)) — mineral

Hematite

Hematite (Fe2O3)

Greenstone (Greenschist) — metamorphic

Greenstone

Greenschist

Blue Sapphire (Corundum (Al2O3 with trace Titanium and Iron)) — mineral

Blue Sapphire

Corundum (Al2O3 with trace Titanium and Iron)

Milky Quartz (Quartz (Silicon Dioxide, SiO2)) — mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Obsidian (Volcanic Glass (SiO2 - Silicon Dioxide with impurities)) — igneous

Obsidian

Volcanic Glass (SiO2 - Silicon Dioxide with impurities)

Ferruginous Quartz (Quartz (Silicon Dioxide, SiO2) with iron oxide inclusions) — mineral

Ferruginous Quartz

Quartz (Silicon Dioxide, SiO2) with iron oxide inclusions

Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Chert

Microcrystalline Quartz (SiO2)

Milky Quartz (Quartz (Silicon Dioxide, SiO2)) — mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Quartz Druze (Silicon Dioxide (SiO2)) — mineral

Quartz Druze

Silicon Dioxide (SiO2)

Banded Agate (specifically Botryoidal/Orbicular Agate) (Silicon Dioxide (SiO2)) — Mineral (variety of Chalcedony/Quartz)

Banded Agate (specifically Botryoidal/Orbicular Agate)

Silicon Dioxide (SiO2)

Mineral (variety of Chalcedony/Quartz)

Chert (Nodule) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Nodule)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Plagioclase Feldspar (specifically Albite/Oligoclase) ((Na,Ca)(Si,Al)4O8) — mineral

Plagioclase Feldspar (specifically Albite/Oligoclase)

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

Gastropod Steinkern (Fossil Snail Internal Mold) (Class Gastropoda (Internal Mold)) — sedimentary

Gastropod Steinkern (Fossil Snail Internal Mold)

Class Gastropoda (Internal Mold)

Ammonite Fossil (Ammonoidea (Calcium carbonate - CaCO3)) — sedimentary

Ammonite Fossil

Ammonoidea (Calcium carbonate - CaCO3)

Iridescent Ammonite (Ammonoidea (Species: likely Cleoniceras or Desmoceras); Mineral: Aragonite/Ammolite (CaCO3)) — sedimentary (fossilized)

Iridescent Ammonite

Ammonoidea (Species: likely Cleoniceras or Desmoceras); Mineral: Aragonite/Ammolite (CaCO3)

sedimentary (fossilized)

White Precious Opal (Hydrated Silica (SiO2·nH2O)) — mineral

White Precious Opal

Hydrated Silica (SiO2·nH2O)

Granite Pebble (River Rock) (Phaneritic Felsic Igneous Rock) — igneous

Granite Pebble (River Rock)

Phaneritic Felsic Igneous Rock

Chert (specifically Yellow or River Chert) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Yellow or River Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Citrine (Silicon dioxide (SiO2)) — mineral

Citrine

Silicon dioxide (SiO2)

Agate (specifically, likely a geode slice or nodule) (Agate (a variety of Chalcedony, with chemical formula SiO2)) — Mineral

Agate (specifically, likely a geode slice or nodule)

Agate (a variety of Chalcedony, with chemical formula SiO2)

Red Jasper (Jasper (Silicon Dioxide, SiO2)) — sedimentary

Red Jasper

Jasper (Silicon Dioxide, SiO2)

Milky Quartz (Quartz (Silicon Dioxide, SiO2)) — mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Amber (Succinite (Formula: C10H16O)) — mineral

Amber

Succinite (Formula: C10H16O)

Hematite (Iron(III) oxide (Fe2O3)) — mineral

Hematite

Iron(III) oxide (Fe2O3)

White Quartz Pebble (Quartz (Silicon Dioxide - SiO2)) — mineral

White Quartz Pebble

Quartz (Silicon Dioxide - SiO2)

Coquina / Fossiliferous Limestone (Fossiliferous Calcarenite (Calcium carbonate, CaCO3)) — sedimentary

Coquina / Fossiliferous Limestone

Fossiliferous Calcarenite (Calcium carbonate, CaCO3)

Aquamarine (Beryllium aluminum silicate (Be3Al2Si6O18)) — mineral

Aquamarine

Beryllium aluminum silicate (Be3Al2Si6O18)

River Pebbles (Sandstone and Quartzite) (SiO2 (Quartz) dominated clastic rocks) — sedimentary and metamorphic

River Pebbles (Sandstone and Quartzite)

SiO2 (Quartz) dominated clastic rocks

sedimentary and metamorphic

Lava Rock (Scoria) (Scoria (highly vesicular basaltic rock)) — igneous

Lava Rock (Scoria)

Scoria (highly vesicular basaltic rock)

Chert (Flint Nodules) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Flint Nodules)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert Nodule (with Flint core) (Sedimentary Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert Nodule (with Flint core)

Sedimentary Cryptocrystalline Quartz (SiO2)

Jasper Agate (Chalcedony (Silicon Dioxide - SiO2)) — mineral

Jasper Agate

Chalcedony (Silicon Dioxide - SiO2)

Quartz (Chert/Chalcedony Variety) (Silicon Dioxide (SiO2)) — mineral

Quartz (Chert/Chalcedony Variety)

Silicon Dioxide (SiO2)

Pink Feldspar (Orthoclase (KAlSi3O8) or Microcline) — mineral

Pink Feldspar

Orthoclase (KAlSi3O8) or Microcline

Native Copper (Penny specimen) (Native Copper (Cu)) — mineral

Native Copper (Penny specimen)

Native Copper (Cu)

Gold (Native Gold (Au)) — mineral

Gold

Native Gold (Au)

Fluorite (Calcium Fluoride (CaF2)) — mineral

Fluorite

Calcium Fluoride (CaF2)

Sandstone (likely Ferruginous) (Arenite (SiO2 with iron oxide impurities)) — sedimentary

Sandstone (likely Ferruginous)

Arenite (SiO2 with iron oxide impurities)

Quartzite Arrowhead (Archaeological Lithic) (Recrystallized Quartz (SiO2)) — metamorphic

Quartzite Arrowhead (Archaeological Lithic)

Recrystallized Quartz (SiO2)

Milky Quartz Pebble (Quartz (Silicon Dioxide, SiO2)) — mineral

Milky Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Granite (Phaneritic Intrusive Igneous Rock (primarily composed of SiO2, Al2O3, K2O, Na2O)) — igneous

Granite

Phaneritic Intrusive Igneous Rock (primarily composed of SiO2, Al2O3, K2O, Na2O)