Rock Identifier

Category

Sedimentary (Volcanic)

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

Jasper (Chalcedony (cryptocrystalline quartz), SiO2) — Sedimentary

Jasper

Chalcedony (cryptocrystalline quartz), SiO2

Lava Rock with Fabric Impression (Scoria or Basalt with anthropogenic impressions) — igneous

Lava Rock with Fabric Impression

Scoria or Basalt with anthropogenic impressions

Fire Agate (Chalcedony (Silicon Dioxide, SiO2) with Limonite/Goethite) — mineral

Fire Agate

Chalcedony (Silicon Dioxide, SiO2) with Limonite/Goethite

Basalt (Mafic Igneous Rock) — igneous

Basalt

Mafic Igneous Rock

Pumice (Pumice (Vesicular felsic extrusive igneous rock)) — igneous

Pumice

Pumice (Vesicular felsic extrusive igneous rock)

Red Jasper (SiO2 (Silicon Dioxide with Iron Oxide inclusions)) — sedimentary/mineral

Red Jasper

SiO2 (Silicon Dioxide with Iron Oxide inclusions)

sedimentary/mineral

Unidentified Rock Fragment (Unknown) — Rock

Unidentified Rock Fragment

Unknown

Amygdaloidal Basalt (Amygdaloidal Basalt containing Zeolite or Quartz (SiO2/Silicates)) — igneous

Amygdaloidal Basalt

Amygdaloidal Basalt containing Zeolite or Quartz (SiO2/Silicates)

Black Obsidian (Obsidian, SiO2 (amorphous)) — Igneous rock (Volcanic glass)

Black Obsidian

Obsidian, SiO2 (amorphous)

Igneous rock (Volcanic glass)

Lava Rock (Scoria) (Scoria (Vesicular Basalt)) — igneous

Lava Rock (Scoria)

Scoria (Vesicular Basalt)

Wishing Stone (Basalt or Siltstone with Quartz/Calcite Vein) (Basalt (SiO2+MgO+FeO) or Siltstone with a Quartz (SiO2) or Calcite (CaCO3) vein) — igneous or sedimentary

Wishing Stone (Basalt or Siltstone with Quartz/Calcite Vein)

Basalt (SiO2+MgO+FeO) or Siltstone with a Quartz (SiO2) or Calcite (CaCO3) vein

igneous or sedimentary

Basalt with Quartz Vein (Mafic Igneous Rock (SiO2 filling)) — igneous

Basalt with Quartz Vein

Mafic Igneous Rock (SiO2 filling)

Basalt (Basalt (composition of plagioclase, pyroxene, and olivine)) — igneous

Basalt

Basalt (composition of plagioclase, pyroxene, and olivine)

Basalt (Mafic igneous rock (primarily Plagioclase feldspar and Pyroxene)) — igneous

Basalt

Mafic igneous rock (primarily Plagioclase feldspar and Pyroxene)

Basalt with Vesicular Texture (Basalt (SiO2 range 45-52%)) — igneous

Basalt with Vesicular Texture

Basalt (SiO2 range 45-52%)

Druzy Quartz on Vesicular Basalt (Silicon Dioxide (SiO2) in an extrusive Mafic igneous host rock) — igneous

Druzy Quartz on Vesicular Basalt

Silicon Dioxide (SiO2) in an extrusive Mafic igneous host rock

Quartz Druse (on Chalcedony/Agate base) (Silicon Dioxide (SiO2)) — mineral

Quartz Druse (on Chalcedony/Agate base)

Silicon Dioxide (SiO2)

Amygdaloidal Basalt (Amygdaloidal Basalt (extrusive volcanic rock)) — Igneous

Amygdaloidal Basalt

Amygdaloidal Basalt (extrusive volcanic rock)

Basalt (River Pebble) (Extrusive mafic igneous rock) — igneous

Basalt (River Pebble)

Extrusive mafic igneous rock

Basalt (Basalt (Mafic igneous rock)) — igneous

Basalt

Basalt (Mafic igneous rock)

Rhyolite (Porphyritic) (Rhyolite (Felsic Extrusive Igneous Rock)) — igneous

Rhyolite (Porphyritic)

Rhyolite (Felsic Extrusive Igneous Rock)

Amygdaloidal Basalt (Amygdaloidal Basalt) — igneous

Amygdaloidal Basalt

Amygdaloidal Basalt

Pumice (Pumice (volcanic glass foam)) — igneous

Pumice

Pumice (volcanic glass foam)

Pumice (Pumicite) — igneous

Pumice

Pumicite

Pumice (Pumice (Amorphous volcanic glass)) — igneous

Pumice

Pumice (Amorphous volcanic glass)

Peridotite (with Olivine) (Peridotite (rich in Olivine, (Mg,Fe)2SiO4)) — igneous

Peridotite (with Olivine)

Peridotite (rich in Olivine, (Mg,Fe)2SiO4)

Basalt (Polished pebble) (Basalt (Aphanitic mafic volcanic rock)) — igneous

Basalt (Polished pebble)

Basalt (Aphanitic mafic volcanic rock)

Amygdaloidal Basalt with Epidote (Vesicular Basalt with secondary Epidote/Quartz mineral infill) — igneous

Amygdaloidal Basalt with Epidote

Vesicular Basalt with secondary Epidote/Quartz mineral infill

Basalt with Porphyritic Texture (Porphyritic Basalt) — igneous

Basalt with Porphyritic Texture

Porphyritic Basalt

Vesicular Basalt with Lichen (Vesicular Basalt) — igneous

Vesicular Basalt with Lichen

Vesicular Basalt

Olivine in Basalt matrix (Peridotite (Mg, Fe)2SiO4) — igneous

Olivine in Basalt matrix

Peridotite (Mg, Fe)2SiO4

Basalt (Polished) (Extrusive mafic igneous rock) — igneous

Basalt (Polished)

Extrusive mafic igneous rock

Basalt (River Pebble) (Extrusive Magic Igneous Rock (Mainly Plagioclase and Pyroxene)) — igneous

Basalt (River Pebble)

Extrusive Magic Igneous Rock (Mainly Plagioclase and Pyroxene)

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

Peridot in Basalt

Olivine ((Mg, Fe)2SiO4) in Basalt

Olivine (Peridotite) ((Mg,Fe)2SiO4 (Magnesium Iron Silicate)) — igneous

Olivine (Peridotite)

(Mg,Fe)2SiO4 (Magnesium Iron Silicate)

Basalt (River Stone) (Extrusive Mafic Igneous Rock (Basalt)) — igneous

Basalt (River Stone)

Extrusive Mafic Igneous Rock (Basalt)

Vesicular Basalt (Extrusive Mafic Igneous Rock (primarily Plagioclase Feldspar and Pyroxene)) — igneous

Vesicular Basalt

Extrusive Mafic Igneous Rock (primarily Plagioclase Feldspar and Pyroxene)

Basalt Pebble (Vesicular Basalt) — igneous

Basalt Pebble

Vesicular Basalt

Pumice (Pumice (Vitreous pyroclastic rock)) — igneous

Pumice

Pumice (Vitreous pyroclastic rock)

Quartz Geode (partially formed/chalcedony with iron staining) (Quartz (SiO2) with Chalcedony (cryptocrystalline quartz) and likely Iron Oxides/Hydroxides) — Mineral/Sedimentary Rock Feature

Quartz Geode (partially formed/chalcedony with iron staining)

Quartz (SiO2) with Chalcedony (cryptocrystalline quartz) and likely Iron Oxides/Hydroxides

Mineral/Sedimentary Rock Feature

Vesicular Basalt (Basalt with vesicular texture) — igneous

Vesicular Basalt

Basalt with vesicular texture

Obsidian (Obsidian (Volcanic Glass)) — igneous

Obsidian

Obsidian (Volcanic Glass)