Rock Identifier

Category

Sedimentary Or Igneous (Secondary Formation)

Browse sedimentary or igneous (secondary formation) specimens identified by the Rock Identifier community.

Limonite (Iron Ore) (Limonite (FeO(OH)·nH2O)) — mineral

Limonite (Iron Ore)

Limonite (FeO(OH)·nH2O)

Sandstone-based Concrete Fragment (Cementitious Composite with Sedimentary Aggregate) — sedimentary (man-made/anthropogenic)

Sandstone-based Concrete Fragment

Cementitious Composite with Sedimentary Aggregate

sedimentary (man-made/anthropogenic)

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

Obsidian

Volcanic glass (SiO2 - Silicon Dioxide with impurities)

Iron Meteorite Fragment (Siderite (Geological term for iron meteorite class - Fe/Ni alloy)) — igneous

Iron Meteorite Fragment

Siderite (Geological term for iron meteorite class - Fe/Ni alloy)

Green Moss Agate (Agate (Silicon Dioxide - SiO2) with inclusions of hornblende or chlorite) — mineral

Green Moss Agate

Agate (Silicon Dioxide - SiO2) with inclusions of hornblende or chlorite

Glass (Amorphous Silicon Dioxide (SiO2)) — mineraloid

Glass

Amorphous Silicon Dioxide (SiO2)

Quartz (Citrine or Iron-Stained variety) (Silicon Dioxide (SiO2)) — mineral

Quartz (Citrine or Iron-Stained variety)

Silicon Dioxide (SiO2)

Rough Rose Quartz (Silicon Dioxide (SiO2) with trace amounts of Titanium, Iron, or Manganese) — mineral

Rough Rose Quartz

Silicon Dioxide (SiO2) with trace amounts of Titanium, Iron, or Manganese

Chert (Common Opal variant) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Common Opal variant)

Silicon Dioxide (SiO2)

Chert (containing Orbicular/Agate patterns) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (containing Orbicular/Agate patterns)

Microcrystalline Quartz (SiO2)

Red Jasper (Silicon Dioxide (SiO2) with Hematite inclusions) — sedimentary

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

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

Amygdaloidal Basalt

Amygdaloidal Basalt (Mafic Extrusive volcanic rock)

Microcrystalline Limestone Pebble (Carbonate sedimentary rock (Calcium Carbonate, CaCO3)) — sedimentary

Microcrystalline Limestone Pebble

Carbonate sedimentary rock (Calcium Carbonate, CaCO3)

Petoskey Stone (Hexagonaria percarinata) — sedimentary

Petoskey Stone

Hexagonaria percarinata

Granite Pebble (Intrusive Felsic Igneous Rock (primarily SiO2 with Al2O3, K2O, Na2O)) — igneous

Granite Pebble

Intrusive Felsic Igneous Rock (primarily SiO2 with Al2O3, K2O, Na2O)

Basalt with Quartz/Feldspar Inclusions (Amygdaloidal or Porphyritic Mafic Volcanic Rock with Siliceous Veining) — igneous

Basalt with Quartz/Feldspar Inclusions

Amygdaloidal or Porphyritic Mafic Volcanic Rock with Siliceous Veining

Porphyritic Basalt (with Quartz or Calcite inclusion) (Porphyritic Basalt (Matrix: SiO2/MgO/FeO, Phenocryst: likely Quartz or Calcite)) — igneous

Porphyritic Basalt (with Quartz or Calcite inclusion)

Porphyritic Basalt (Matrix: SiO2/MgO/FeO, Phenocryst: likely Quartz or Calcite)

Amygdaloidal Basalt with Quartz/Zeolite Infill (Amygdaloidal Basalt (extrusive volcanic rock with SiO2 or CaAl2Si3O10·3H2O infill)) — igneous

Amygdaloidal Basalt with Quartz/Zeolite Infill

Amygdaloidal Basalt (extrusive volcanic rock with SiO2 or CaAl2Si3O10·3H2O infill)

Red Sandstone (Arenite with Hematite (Fe2O3) cement) — sedimentary

Red Sandstone

Arenite with Hematite (Fe2O3) cement

Porphyritic Basalt (with Amygdales) (Amygdaloidal Porphyritic Basalt) — igneous

Porphyritic Basalt (with Amygdales)

Amygdaloidal Porphyritic Basalt

Red Sandstone (Arenite (Fe2O3-rich)) — sedimentary

Red Sandstone

Arenite (Fe2O3-rich)

Chrysocolla (Hydrated copper phyllosilicate, Cu2-xAlx(H2-xSi2O5)(OH)4·n(H2O)) — mineral

Chrysocolla

Hydrated copper phyllosilicate, Cu2-xAlx(H2-xSi2O5)(OH)4·n(H2O)

Quartz (Iron-stained) (Silicon Dioxide (SiO2)) — mineral

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Limonite (Iron Ore) (Limonite (Hydrated Iron Oxide, FeO(OH)·nH2O)) — Mineral

Limonite (Iron Ore)

Limonite (Hydrated Iron Oxide, FeO(OH)·nH2O)

Chert / Flint (Cryptocrystalline quartz (SiO2)) — Sedimentary

Chert / Flint

Cryptocrystalline quartz (SiO2)

Basalt with Quartz/Feldspar Inclusion (Basalt (containing Silicate minerals such as SiO2 and (Ca,Na)(Al,Si)4O8)) — igneous

Basalt with Quartz/Feldspar Inclusion

Basalt (containing Silicate minerals such as SiO2 and (Ca,Na)(Al,Si)4O8)

Basalt with Quartz/Calcite Inclusions (Mafic Volcanic Rock (Fe-Mg silicate rich)) — igneous

Basalt with Quartz/Calcite Inclusions

Mafic Volcanic Rock (Fe-Mg silicate rich)

Basalt with Quartz Veins (Basalt (composition: SiO2, MgO, FeO, Al2O3, CaO)) — igneous

Basalt with Quartz Veins

Basalt (composition: SiO2, MgO, FeO, Al2O3, CaO)

Quartz Veined Basalt Pebble (Amygdaloidal Basalt with Quartz (SiO2) veining) — igneous

Quartz Veined Basalt Pebble

Amygdaloidal Basalt with Quartz (SiO2) veining

Basalt (River Stone) (Basalt) — igneous

Basalt (River Stone)

Basalt

Granite (Granite (a felsic intrusive igneous rock composed primarily of quartz, feldspar, and mica)) — igneous

Granite

Granite (a felsic intrusive igneous rock composed primarily of quartz, feldspar, and mica)

Ruby (Corundum) (Corundum (Aluminum Oxide with Chromium), Al2O3:Cr) — mineral

Ruby (Corundum)

Corundum (Aluminum Oxide with Chromium), Al2O3:Cr

Sandstone with Liesegang Rings (Arenite with Iron Oxide Concretions) — sedimentary

Sandstone with Liesegang Rings

Arenite with Iron Oxide Concretions

Carnelian (Banded Agate) (Chalcedony (SiO2) with Iron Oxide inclusions) — mineral

Carnelian (Banded Agate)

Chalcedony (SiO2) with Iron Oxide inclusions

Granite (Granite (Felsic Plutonic Rock)) — igneous

Granite

Granite (Felsic Plutonic Rock)

Calcite (Calcite (CaCO3)) — mineral

Calcite

Calcite (CaCO3)

Banded Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert

Microcrystalline Quartz (SiO2)

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

Jasper

Jasper (Silicon Dioxide, SiO2)

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

Chert (often called Flint when dark or found in chalk)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Black Tourmaline (Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)) — Mineral

Black Tourmaline

Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)