Rock Identifier

Category

Sedimentary Rock

Browse sedimentary rock specimens identified by the Rock Identifier community.

Diorite (Diorite (an intrusive igneous rock)) — igneous

Diorite

Diorite (an intrusive igneous rock)

Basalt Pebble (Extrusive Mafic Igneous Rock) — igneous

Basalt Pebble

Extrusive Mafic Igneous Rock

Basalt with Iron Oxides (Mafic Igneous Rock (Mafite)) — igneous

Basalt with Iron Oxides

Mafic Igneous Rock (Mafite)

Basalt Pebble with Quartz Veining (Basalt (extrusive volcanic rock)) — igneous

Basalt Pebble with Quartz Veining

Basalt (extrusive volcanic rock)

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

Basalt (River Pebble)

Extrusive mafic igneous rock

Basalt Pebble (Extrusive Mafic Volcanic Rock) — igneous

Basalt Pebble

Extrusive Mafic Volcanic Rock

Basalt River Stone (Basalt (Mafic volcanic rock)) — igneous

Basalt River Stone

Basalt (Mafic volcanic rock)

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

Basalt Pebble

Basalt (Mafic volcanic rock)

Basalt (Extrusive mafic igneous rock) — igneous

Basalt

Extrusive mafic igneous rock

Granite (Granite (Felsic Plutonic Rock)) — igneous

Granite

Granite (Felsic Plutonic Rock)

Basalt (Extrusive mafic igneous rock) — igneous

Basalt

Extrusive mafic igneous rock

Basalt Pebble (Extrusive Mafic Igneous Rock) — igneous

Basalt Pebble

Extrusive Mafic Igneous Rock

Basalt (Extrusive mafic igneous rock) — igneous

Basalt

Extrusive mafic igneous rock

Gneiss (likely) (Gneiss) — Metamorphic

Gneiss (likely)

Gneiss

Granite (Granite (Felsic Plutonic Rock)) — Igneous

Granite

Granite (Felsic Plutonic 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

Quartz Vein in Host Rock (Silicon Dioxide (SiO2) within Metasedimentary or Igneous matrix) — mineral

Quartz Vein in Host Rock

Silicon Dioxide (SiO2) within Metasedimentary or Igneous matrix

Ocean Jasper (Orbicular Jasper (Silicon Dioxide with impurities), SiO2) — mineral

Ocean Jasper

Orbicular Jasper (Silicon Dioxide with impurities), SiO2

Quartz (Milky/Yellowish variety) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky/Yellowish variety)

Silicon Dioxide (SiO2)

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

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Amygdaloidal Basalt

Amygdaloidal Basalt (Mafic Extrusive volcanic rock)

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

Olivine in Basalt matrix

Peridotite (Mg, Fe)2SiO4

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Basalt Porphyry (Porphyritic Basalt) — igneous

Basalt Porphyry

Porphyritic Basalt

Granite (with alteration) (Granite (Felsic intrusive igneous rock)) — igneous

Granite (with alteration)

Granite (Felsic intrusive igneous rock)

Basalt (Basalt (principally Plagioclase and Pyroxene)) — igneous

Basalt

Basalt (principally Plagioclase and Pyroxene)

Basalt River Stone (Aphanitic Mafic Igneous Rock (primarily Plagioclase and Pyroxene)) — igneous

Basalt River Stone

Aphanitic Mafic Igneous Rock (primarily Plagioclase and Pyroxene)

Basalt (Stream-worn Cobble) (Mafic Igneous Rock (primarily Plagioclase and Pyroxene)) — igneous

Basalt (Stream-worn Cobble)

Mafic Igneous Rock (primarily Plagioclase and Pyroxene)

Basalt with Epidote Veins (Mafic Igneous Rock (Basalt)) — igneous

Basalt with Epidote Veins

Mafic Igneous Rock (Basalt)

Serpentinite (Serpentine Rock) (Primarily composed of serpentine group minerals, such as antigorite, chrysotile, and lizardite. Chemical formula for serpentine minerals is (Mg,Fe)3Si2O5(OH)4.) — Metamorphic

Serpentinite (Serpentine Rock)

Primarily composed of serpentine group minerals, such as antigorite, chrysotile, and lizardite. Chemical formula for serpentine minerals is (Mg,Fe)3Si2O5(OH)4.

Quartz on Greenstone (Silicon Dioxide (SiO2) on Altered Igneous Geologic Unit) — metamorphic

Quartz on Greenstone

Silicon Dioxide (SiO2) on Altered Igneous Geologic Unit

Rose Quartz (Silicon Dioxide (SiO2)) — mineral

Rose Quartz

Silicon Dioxide (SiO2)

Milky Quartz with Iron Staining (Quartz (Silicon Dioxide, SiO2)) — mineral

Milky Quartz with Iron Staining

Quartz (Silicon Dioxide, SiO2)

Scoria (with likely iron oxidation) (Scoria (Basaltic Scoria)) — igneous

Scoria (with likely iron oxidation)

Scoria (Basaltic Scoria)

Tiger's Eye (Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)) — metamorphic

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)

Snowflake Obsidian (Spherulitic Volcanic Glass (primarily SiO2 with Cristobalite inclusions)) — igneous

Snowflake Obsidian

Spherulitic Volcanic Glass (primarily SiO2 with Cristobalite inclusions)

Granite Cobble (Plutonic Igneous Rock (Granitic)) — igneous

Granite Cobble

Plutonic Igneous Rock (Granitic)

Rose Quartz (Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese) — mineral

Rose Quartz

Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese

Quartz Vein in Host Rock (Gabbro or Basalt) (Silicon Dioxide (SiO2) with Mafic Silicates) — metamorphic/igneous

Quartz Vein in Host Rock (Gabbro or Basalt)

Silicon Dioxide (SiO2) with Mafic Silicates

metamorphic/igneous

Vesicular Basalt (or Scoraceous Basalt) (Basalt with vesicular texture) — igneous

Vesicular Basalt (or Scoraceous Basalt)

Basalt with vesicular texture

Vesicular Basalt (or Scoria) (Vesicular Basalt) — igneous

Vesicular Basalt (or Scoria)

Vesicular Basalt

Basalt Scoria (Vesicular Basalt) — igneous

Basalt Scoria

Vesicular Basalt