Rock Identifier

Category

Sedimentary (Volcanic)

Browse sedimentary (volcanic) specimens identified by the Rock Identifier community.

Mahogany Obsidian (Volcanic Glass (SiO2 + Fe2O3)) — igneous

Mahogany Obsidian

Volcanic Glass (SiO2 + Fe2O3)

Orange Calcite (Calcium Carbonate (CaCO3)) — mineral

Orange Calcite

Calcium Carbonate (CaCO3)

Jasper (Iron-rich) (Silicon Dioxide (SiO2) with Fe2O3 (Hematite) impurities) — sedimentary

Jasper (Iron-rich)

Silicon Dioxide (SiO2) with Fe2O3 (Hematite) impurities

Chert (Chert Nodule with Chalky Cortex) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (Chert Nodule with Chalky Cortex)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Blue Apatite (Fluorapatite (Ca5(PO4)3F)) — mineral

Blue Apatite

Fluorapatite (Ca5(PO4)3F)

Halite (Rock Salt) (Halite (Sodium Chloride, NaCl)) — mineral

Halite (Rock Salt)

Halite (Sodium Chloride, NaCl)

Orange Calcite (Cleavage Rhomb) (Calcite (Calcium Carbonate, CaCO3)) — mineral

Orange Calcite (Cleavage Rhomb)

Calcite (Calcium Carbonate, CaCO3)

Manganese Ore (Psilomelane/Pyrolusite) (Psilomelane ((Ba,H2O)2Mn5O10) and Pyrolusite (MnO2)) — Mineral

Manganese Ore (Psilomelane/Pyrolusite)

Psilomelane ((Ba,H2O)2Mn5O10) and Pyrolusite (MnO2)

Obsidian (Volcanic Glass (predominantly SiO2 – Silicon Dioxide, but non-crystalline)) — Igneous

Obsidian

Volcanic Glass (predominantly SiO2 – Silicon Dioxide, but non-crystalline)

Pumice (Pumiceous rhyolite) — igneous

Pumice

Pumiceous rhyolite

Black Obsidian (Volcanic Glass (70–75% SiO2 plus MgO, Fe3O4)) — igneous

Black Obsidian

Volcanic Glass (70–75% SiO2 plus MgO, Fe3O4)

Obsidian (Obsidian (Volcanic Glass, SiO2 + impurities)) — igneous

Obsidian

Obsidian (Volcanic Glass, SiO2 + impurities)

Basalt (Basalt (Mafic volcanic rock)) — igneous

Basalt

Basalt (Mafic volcanic rock)

Obsidian (Volcanic Glass (SiO2 + impurities)) — igneous

Obsidian

Volcanic Glass (SiO2 + impurities)

Scoria (Basaltic) (Vesicular Basalt) — igneous

Scoria (Basaltic)

Vesicular Basalt

Pumice (Vesicular Rhyolite (highly vesicular igneous volcanic rock)) — igneous

Pumice

Vesicular Rhyolite (highly vesicular igneous volcanic rock)

Peridot (Olivine ((Mg, Fe)2SiO4)) — mineral

Peridot

Olivine ((Mg, Fe)2SiO4)

Banded Agate (Cryptocrystalline Silica (SiO2)) — mineral

Banded Agate

Cryptocrystalline Silica (SiO2)

Banded Agate (Chalcedony (SiO2) with microcrystalline quartz) — mineral

Banded Agate

Chalcedony (SiO2) with microcrystalline quartz

Basalt (River Stone) (Basalt) — igneous

Basalt (River Stone)

Basalt

Vesicular Basalt (Aphanitic Mafic Igneous Rock (with Vesicular Texture)) — igneous

Vesicular Basalt

Aphanitic Mafic Igneous Rock (with Vesicular Texture)

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Blue Apatite (Apatite (Calcium Phosphate) - Ca5(PO4)3(F,Cl,OH)) — mineral

Blue Apatite

Apatite (Calcium Phosphate) - Ca5(PO4)3(F,Cl,OH)

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

Obsidian

Volcanic glass (SiO2 - Silicon Dioxide with impurities)

Fossiliferous Limestone with Brachiopod (Phylum Brachiopoda in calcitic matrix) — sedimentary

Fossiliferous Limestone with Brachiopod

Phylum Brachiopoda in calcitic matrix

Basalt (Extrusive mafic igneous rock) — igneous

Basalt

Extrusive mafic igneous rock

Basalt Porphyry (River Pebble) (Porphyritic Basalt) — igneous

Basalt Porphyry (River Pebble)

Porphyritic Basalt

Sandstone (with ripple marks) (Arenite / Quartz Sandstone) — sedimentary

Sandstone (with ripple marks)

Arenite / Quartz Sandstone

Carnelian (Chalcedony (SiO₂)) — mineral

Carnelian

Chalcedony (SiO₂)

Peridot (Olivine ((Mg, Fe)2SiO4)) — mineral

Peridot

Olivine ((Mg, Fe)2SiO4)

Knightia Fossil in Limestone (Knightia eocaena in micritic limestone) — sedimentary

Knightia Fossil in Limestone

Knightia eocaena in micritic limestone

Obsidian (Amorphous volcanic glass (70-75% SiO2)) — igneous

Obsidian

Amorphous volcanic glass (70-75% SiO2)

Vesicular Basalt (or Scoria) (Vesicular Basalt (Aphanitic-vesicular volcanic rock)) — igneous

Vesicular Basalt (or Scoria)

Vesicular Basalt (Aphanitic-vesicular volcanic rock)

Sandstone (Arenite (Sedimentary rock composed of sand-sized grains, primarily SiO2)) — sedimentary

Sandstone

Arenite (Sedimentary rock composed of sand-sized grains, primarily SiO2)

Obsidian (Obsidian (Amorphous volcanic glass)) — igneous

Obsidian

Obsidian (Amorphous volcanic glass)

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

Basalt

Basalt (Aphanitic Mafic Igneous Rock)

Andesite Porphyry (Andesite (Intermediate Volcanic Rock)) — igneous

Andesite Porphyry

Andesite (Intermediate Volcanic Rock)

Vesicular Basalt with Opal or Quartz (Vesicular Basalt (Amorphous SiO2.nH2O if Opal)) — igneous

Vesicular Basalt with Opal or Quartz

Vesicular Basalt (Amorphous SiO2.nH2O if Opal)

Amygdaloidal Rhyolite (Amygdaloidal felsic extrusive rock) — igneous

Amygdaloidal Rhyolite

Amygdaloidal felsic extrusive rock

Kimberlite (Kimberlite (Potassic ultramafic volcanic rock)) — igneous

Kimberlite

Kimberlite (Potassic ultramafic volcanic rock)

Pumice (Extrusive volcanic rock (Vesicular Rhyolite/Dacite/Andesite)) — igneous

Pumice

Extrusive volcanic rock (Vesicular Rhyolite/Dacite/Andesite)

Pyrite (Fool's Gold) (Iron Sulfide (FeS2)) — mineral

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)