Rock Identifier

Category

Organic (Often Found By Beachcombers)

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

Conglomerate (Conglomerate (clastic sedimentary rock)) — sedimentary

Conglomerate

Conglomerate (clastic sedimentary rock)

Sandstone with Quarzite clasts (Arenite (SiO2 based)) — sedimentary

Sandstone with Quarzite clasts

Arenite (SiO2 based)

Rhyolite (Rhyolite (High-silica volcanic rock)) — igneous

Rhyolite

Rhyolite (High-silica volcanic rock)

Dyed Chalcedony (Agate) (Silicon Dioxide (SiO2) with artificial pigment) — mineral

Dyed Chalcedony (Agate)

Silicon Dioxide (SiO2) with artificial pigment

Chert (Field Stone) (Chert (SiO2)) — sedimentary

Chert (Field Stone)

Chert (SiO2)

Sandstone (lithic wacke) (Arenite / Lithic Wacke (mostly SiO2 with rock fragments)) — sedimentary

Sandstone (lithic wacke)

Arenite / Lithic Wacke (mostly SiO2 with rock fragments)

Rough Quartz (Milky Quartz Pebbles) (Silicon Dioxide (SiO2)) — mineral

Rough Quartz (Milky Quartz Pebbles)

Silicon Dioxide (SiO2)

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

Jasper

Jasper (Silica/Silicon Dioxide, SiO2)

Limestone (Calcium Carbonate (CaCO3)) — Sedimentary

Limestone

Calcium Carbonate (CaCO3)

Conglomerate (Conglomerate (clastic sedimentary rock)) — sedimentary

Conglomerate

Conglomerate (clastic sedimentary rock)

Quartzite (River Cobble) (SiO2 (Quartz-rich Metamorphic Rock)) — metamorphic

Quartzite (River Cobble)

SiO2 (Quartz-rich Metamorphic Rock)

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

Jasper

Jasper (Silicon Dioxide, SiO2)

Sandstone (Ferruginous) (Arenite (primarily SiO2 with Fe2O3 staining)) — sedimentary

Sandstone (Ferruginous)

Arenite (primarily SiO2 with Fe2O3 staining)

Sandstone (likely Arkosic) (Arenite (SiO2 with KAlSi3O8)) — sedimentary

Sandstone (likely Arkosic)

Arenite (SiO2 with KAlSi3O8)

Milky Quartz with Iron Inclusions (Silicon Dioxide (SiO2)) — mineral

Milky Quartz with Iron Inclusions

Silicon Dioxide (SiO2)

Sandstone (specifically Lithic or Quartz Arenite) (Arenite (composed primarily of SiO2)) — sedimentary

Sandstone (specifically Lithic or Quartz Arenite)

Arenite (composed primarily of SiO2)

Sandstone (Clastic Sedimentary Rock (composed of SiO2 grains)) — sedimentary

Sandstone

Clastic Sedimentary Rock (composed of SiO2 grains)

Blue Agate (likely dyed) (Silicon Dioxide (SiO2)) — mineral

Blue Agate (likely dyed)

Silicon Dioxide (SiO2)

River Stone (Quartzite/Siltstone mixture) (Silicon Dioxide (SiO2) based metamorphosed sandstone) — metamorphic or sedimentary

River Stone (Quartzite/Siltstone mixture)

Silicon Dioxide (SiO2) based metamorphosed sandstone

metamorphic or sedimentary

Porphyry (Porphyritic Rhyolite or Andesite) — igneous

Porphyry

Porphyritic Rhyolite or Andesite

Sandstone (Quartzose Sandstone) (Clastic Sedimentary Rock (primarily SiO2 with Fe2O3 staining)) — sedimentary

Sandstone (Quartzose Sandstone)

Clastic Sedimentary Rock (primarily SiO2 with Fe2O3 staining)

Blue Chalcedony (Silicon Dioxide (SiO2)) — mineral

Blue Chalcedony

Silicon Dioxide (SiO2)

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Quartz / Common Opal (Silicon Dioxide (SiO2)) — mineral

Quartz / Common Opal

Silicon Dioxide (SiO2)

Sandstone (with Iron Staining) (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone (with Iron Staining)

Clastic sedimentary rock (primarily SiO2)

Basalt (Basalt (Mafic igneous rock)) — igneous

Basalt

Basalt (Mafic igneous rock)

Amethyst (Amethyst (Silicon Dioxide - SiO2 with Iron impurities)) — mineral

Amethyst

Amethyst (Silicon Dioxide - SiO2 with Iron impurities)

Pegmatite (with smoky quartz and tourmaline/biotite) (Pegmatitic Granite) — igneous

Pegmatite (with smoky quartz and tourmaline/biotite)

Pegmatitic Granite

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

Clear Quartz

Quartz (Silicon Dioxide, SiO2)

Sandstone (Arenite (composed primarily of SiO2)) — sedimentary

Sandstone

Arenite (composed primarily of SiO2)

Sulfur (on Matrix) (Native Sulfur (S8)) — mineral

Sulfur (on Matrix)

Native Sulfur (S8)

Sandstone (Clastic Sedimentary Rock (primarily Quartz, SiO2)) — sedimentary

Sandstone

Clastic Sedimentary Rock (primarily Quartz, SiO2)

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Carnelian (SiO2 (Silicon Dioxide) - Translucent Chalcedony) — mineral

Carnelian

SiO2 (Silicon Dioxide) - Translucent Chalcedony

Iron Meteorite (Siderite (Iron-Nickel Alloy), predominantly Kamacite and Taenite (Fe, Ni)) — mineral

Iron Meteorite

Siderite (Iron-Nickel Alloy), predominantly Kamacite and Taenite (Fe, Ni)

Zoisite with Ruby (Anyolite (Ca2Al3(SiO4)3(OH) with Al2O3:Cr)) — metamorphic

Zoisite with Ruby

Anyolite (Ca2Al3(SiO4)3(OH) with Al2O3:Cr)

Quartz Crystal with Inclusions (Silicon Dioxide (SiO2)) — mineral

Quartz Crystal with Inclusions

Silicon Dioxide (SiO2)

Greenschist / Greenstone (Greenschist facies metabasite) — metamorphic

Greenschist / Greenstone

Greenschist facies metabasite

Quartz Geode Pebble (Silicon Dioxide (SiO2)) — mineral

Quartz Geode Pebble

Silicon Dioxide (SiO2)

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

Limonite (Iron Ore)

Limonite (FeO(OH)·nH2O)

Diamond (in a metal ring setting) (Diamond (Pure Carbon, C)) — mineral

Diamond (in a metal ring setting)

Diamond (Pure Carbon, C)

Quartzite Cobble (Metamorphosed Quartz Sandstone (primarily SiO2)) — metamorphic

Quartzite Cobble

Metamorphosed Quartz Sandstone (primarily SiO2)