Rock Identifier

Category

Mineral, Often A Rock Given Its Aggregate Nature

Browse mineral, often a rock given its aggregate nature specimens identified by the Rock Identifier community.

Sandstone (specifically an Iron-Concretion) (Arenite with Iron Oxide (Limonite/Goethite) cementation) — sedimentary

Sandstone (specifically an Iron-Concretion)

Arenite with Iron Oxide (Limonite/Goethite) cementation

Garnet (almandine or pyrope variety) (Silicate mineral Group: (Fe, Mg, Mn, Ca)3(Al, Fe, Cr)2(SiO4)3) — mineral

Garnet (almandine or pyrope variety)

Silicate mineral Group: (Fe, Mg, Mn, Ca)3(Al, Fe, Cr)2(SiO4)3

Quartz (Quartzite fragment) (Silicon Dioxide (SiO2)) — mineral

Quartz (Quartzite fragment)

Silicon Dioxide (SiO2)

Milky Quartz (with trace inclusions) (Silicon Dioxide (SiO2)) — mineral

Milky Quartz (with trace inclusions)

Silicon Dioxide (SiO2)

Yellow Jasper (Silicon Dioxide (SiO2) with iron oxide inclusions) — sedimentary

Yellow Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Granite (Granite (a common rock type, not a single mineral with a formula. Composed primarily of quartz, feldspar, and mica/amphibole).) — igneous

Granite

Granite (a common rock type, not a single mineral with a formula. Composed primarily of quartz, feldspar, and mica/amphibole).

Sandstone (Arenite (composed primarily of SiO2)) — sedimentary

Sandstone

Arenite (composed primarily of SiO2)

Basalt (Porphyritic Basalt) (Porphyritic Basalt (Mafic volcanic rock)) — igneous

Basalt (Porphyritic Basalt)

Porphyritic Basalt (Mafic volcanic rock)

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

Granite

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

Ironstone Concretion (Siderite or Limonite Concretion) — sedimentary

Ironstone Concretion

Siderite or Limonite Concretion

Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Chert (often called Flint when dark) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often called Flint when dark)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Chert (variant of microcrystalline quartz)) — Sedimentary

Chert

Chert (variant of microcrystalline quartz)

Amygdaloidal Basalt (Amygdaloidal Basalt (Mafic volcanic rock)) — igneous

Amygdaloidal Basalt

Amygdaloidal Basalt (Mafic volcanic rock)

Red Jasper (possibly Agatized Jasper) (Jasper (Silicon Dioxide, SiO2 with Fe2O3 inclusions)) — sedimentary

Red Jasper (possibly Agatized Jasper)

Jasper (Silicon Dioxide, SiO2 with Fe2O3 inclusions)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Jasper (Iron-stained Chert) (Silicon Dioxide (SiO2) with impurities of Hematite or Goethite) — sedimentary

Jasper (Iron-stained Chert)

Silicon Dioxide (SiO2) with impurities of Hematite or Goethite

Agate (Silicon Dioxide (SiO2)) — mineral

Agate

Silicon Dioxide (SiO2)

Serpentinite (often containing Jadeite/Nephrite) (Antigorite-rich Serpentine Rock, (Mg, Fe)3Si2O5(OH)4) — metamorphic

Serpentinite (often containing Jadeite/Nephrite)

Antigorite-rich Serpentine Rock, (Mg, Fe)3Si2O5(OH)4

Red Sandstone (Arenite (primarily SiO2 with hematite/iron oxide coating)) — sedimentary

Red Sandstone

Arenite (primarily SiO2 with hematite/iron oxide coating)

Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

Sandstone (Arenite (SiO2 primarily)) — sedimentary

Sandstone

Arenite (SiO2 primarily)

Vesicular Basalt (Lava Rock) (Aphanitic Mafic Igneous Rock) — igneous

Vesicular Basalt (Lava Rock)

Aphanitic Mafic Igneous Rock

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Amethyst (Amethyst (Silicon Dioxide, SiO2 + Fe)) — mineral

Amethyst

Amethyst (Silicon Dioxide, SiO2 + Fe)

Gold Nugget (Native Gold (Au)) — mineral

Gold Nugget

Native Gold (Au)

Serpentine (Serpentinite) (Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4) — metamorphic

Serpentine (Serpentinite)

Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4

Sandstone (Ferruginous) (Arenite (complex silicate composition with iron oxides)) — sedimentary

Sandstone (Ferruginous)

Arenite (complex silicate composition with iron oxides)

Sandstone (with banding) (Arenite (primarily SiO2)) — sedimentary

Sandstone (with banding)

Arenite (primarily SiO2)

Schist (Mica Schist (Quartz-Muscovite-Biotite Schist)) — metamorphic

Schist

Mica Schist (Quartz-Muscovite-Biotite Schist)

Mahogany Obsidian (Obsidian (Volcanic Glass) with Hematite/Magnetite inclusions) — igneous

Mahogany Obsidian

Obsidian (Volcanic Glass) with Hematite/Magnetite inclusions

Yellow Quartz (Citrine Quartz Pebble) (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz (Citrine Quartz Pebble)

Silicon Dioxide (SiO2)

Sandstone (Arenite (SiO2 primarily)) — sedimentary

Sandstone

Arenite (SiO2 primarily)

Quartz Geode (Silicon Dioxide (SiO2)) — mineral

Quartz Geode

Silicon Dioxide (SiO2)

Sandstone (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone

Clastic sedimentary rock (primarily SiO2)

Basalt with Iron Oxidation (Mafic Igneous Basalt) — igneous

Basalt with Iron Oxidation

Mafic Igneous Basalt

Carnelian (Carnelian (a variety of Chalcedony, which is a microcrystalline quartz, SiO2)) — Mineral (variety of Chalcedony)

Carnelian

Carnelian (a variety of Chalcedony, which is a microcrystalline quartz, SiO2)

Mineral (variety of Chalcedony)

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

Milky Quartz Pebble

Silicon Dioxide (SiO2)

Chert (Smooth River Pebble) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Smooth River Pebble)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Dolerite (Diabase) (Dolerite / Diabase) — igneous

Dolerite (Diabase)

Dolerite / Diabase

Basalt Pebble (Basalt) — igneous

Basalt Pebble

Basalt

Sandstone (Ferruginous) (Arenite (primarily SiO2 with iron oxide cement)) — sedimentary

Sandstone (Ferruginous)

Arenite (primarily SiO2 with iron oxide cement)