Rock Identifier

Category

Organic (Often Found By Beachcombers)

Browse organic (often found by beachcombers) specimens identified by the Rock Identifier community.

Trilobite Fossil (Trilobita (Class), likely Phacopid or Asaphid order) — sedimentary

Trilobite Fossil

Trilobita (Class), likely Phacopid or Asaphid order

Ferruginous Siltstone or Mudstone (Ferruginous Siltstone / Goethitic Sandstone) — sedimentary

Ferruginous Siltstone or Mudstone

Ferruginous Siltstone / Goethitic Sandstone

Quartzite Cobble (Quartzite (primarily SiO2)) — metamorphic

Quartzite Cobble

Quartzite (primarily SiO2)

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

Chert (often called Flint or Jasper)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Howlite (Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)) — mineral

Howlite

Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)

Quartzite Pebble (Quartzite (primarily SiO2)) — metamorphic

Quartzite Pebble

Quartzite (primarily SiO2)

Schist (Mica Schist) — metamorphic

Schist

Mica Schist

Hematite (Oolitic or Earthy variety) (Iron(III) oxide (Fe2O3)) — mineral

Hematite (Oolitic or Earthy variety)

Iron(III) oxide (Fe2O3)

Grey Chalcedony (Agate) (Silicon Dioxide (SiO2)) — mineral

Grey Chalcedony (Agate)

Silicon Dioxide (SiO2)

Jasper (Green/Dragon Blood variety) (Silicon Dioxide (SiO2) with iron/clay inclusions) — sedimentary

Jasper (Green/Dragon Blood variety)

Silicon Dioxide (SiO2) with iron/clay inclusions

Basalt (Polished River Stone) (Mafic Volcanic Rock (primarily Plagioclase and Pyroxene)) — Igneous

Basalt (Polished River Stone)

Mafic Volcanic Rock (primarily Plagioclase and Pyroxene)

Basalt (Beach Pebble) (Extrusive mafic volcanic rock) — igneous

Basalt (Beach Pebble)

Extrusive mafic volcanic rock

Gold Nugget (Native Gold (Au)) — mineral

Gold Nugget

Native Gold (Au)

White Chalcedony (Agate) (Silicon Dioxide (SiO2)) — mineral

White Chalcedony (Agate)

Silicon Dioxide (SiO2)

Sodalite (Sodalite - Na8(Al6Si6O24)Cl2) — mineral

Sodalite

Sodalite - Na8(Al6Si6O24)Cl2

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

Fossiliferous Limestone with Brachiopod

Phylum Brachiopoda in calcitic matrix

Chalcedony / Agate (Silicon Dioxide (SiO2)) — mineral

Chalcedony / Agate

Silicon Dioxide (SiO2)

Native Copper Nugget (Native Copper (Cu)) — mineral

Native Copper Nugget

Native Copper (Cu)

Ironstone Concretion / Goethite-Hematite Nodule (Goethite/Hematite (α-FeO(OH) / Fe2O3)) — sedimentary

Ironstone Concretion / Goethite-Hematite Nodule

Goethite/Hematite (α-FeO(OH) / Fe2O3)

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

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Scoria (Vesicular Basalt) (Vesicular Basaltic Andesite) — igneous

Scoria (Vesicular Basalt)

Vesicular Basaltic Andesite

Druzy Quartz on Chalcedony Matrix (Silicon Dioxide (SiO2)) — mineral

Druzy Quartz on Chalcedony Matrix

Silicon Dioxide (SiO2)

Almandine Garnet in Matrix (Almandine, Fe3Al2(SiO4)3) — metamorphic

Almandine Garnet in Matrix

Almandine, Fe3Al2(SiO4)3

Chert Pebble (Yellow/Brown Jasper variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert Pebble (Yellow/Brown Jasper variety)

Microcrystalline Quartz (SiO2)

Diamond (Diamond (pure Carbon, C)) — mineral

Diamond

Diamond (pure Carbon, C)

Black Onyx (Onyx (Silicon Dioxide, SiO2)) — mineral

Black Onyx

Onyx (Silicon Dioxide, SiO2)

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

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

White Agate (Chalcedony) (Chalcedony (SiO2)) — mineral

White Agate (Chalcedony)

Chalcedony (SiO2)

Olivine (Peridot) (Magnesium Iron Silicate (Mg, Fe)2SiO4) — mineral

Olivine (Peridot)

Magnesium Iron Silicate (Mg, Fe)2SiO4

Granite (Alkali-feldspar Granite) (Felsic Plutonic Rock (Primary minerals: Quartz SiO2, Orthoclase KAlSi3O8, Plagioclase (Na,Ca)AlSi3O8)) — igneous

Granite (Alkali-feldspar Granite)

Felsic Plutonic Rock (Primary minerals: Quartz SiO2, Orthoclase KAlSi3O8, Plagioclase (Na,Ca)AlSi3O8)

Quartz (specifically Milky or Clear Quartz) (Silicon Dioxide (SiO2)) — mineral

Quartz (specifically Milky or Clear Quartz)

Silicon Dioxide (SiO2)

Quartzite Cobble (Quartzite (primarily SiO2)) — metamorphic

Quartzite Cobble

Quartzite (primarily SiO2)

Basalt (Basalt (Mafic volcanic rock)) — Igneous

Basalt

Basalt (Mafic volcanic rock)

Scoria (Vesicular Basaltic Glass) — igneous

Scoria

Vesicular Basaltic Glass

Quartzite (Quartzite (mainly SiO2)) — metamorphic

Quartzite

Quartzite (mainly SiO2)

Biotite Schist (with Garnet and Pyrite) (K(Mg,Fe)3AlSi3O10(OH,F)2 (Biotite focus)) — metamorphic

Biotite Schist (with Garnet and Pyrite)

K(Mg,Fe)3AlSi3O10(OH,F)2 (Biotite focus)

Orange Quartzite (with Iron Staining) (Quartzite (SiO2)) — metamorphic

Orange Quartzite (with Iron Staining)

Quartzite (SiO2)

Quartzite River Rock (Quartzite (Silicon Dioxide, SiO2)) — metamorphic

Quartzite River Rock

Quartzite (Silicon Dioxide, SiO2)

Schist (Mica Schist) — metamorphic

Schist

Mica Schist

Quartzite with Gneissic Banding (Quartzite (primarily SiO2) with mafic mineral inclusions) — metamorphic

Quartzite with Gneissic Banding

Quartzite (primarily SiO2) with mafic mineral inclusions

Granite (Granite (Phaneritic Quartz-Feldspar Rock)) — igneous

Granite

Granite (Phaneritic Quartz-Feldspar Rock)

Basalt (Basalt) — igneous

Basalt

Basalt