Rock Identifier

Category

Igneous Or Sedimentary (Water Worn)

Browse igneous or sedimentary (water worn) specimens identified by the Rock Identifier community.

Learn about Igneous Or Sedimentary (Water Worn) in the encyclopedia

Water Opal

Enhydro Quartz

Carbonatite

Clear Beryl

Ice Opal

Hyalite Opal

Iolite

Conglomerate

Jelly Opal

Clear Obsidian

Coldwater Agate

Clear Tourmaline

Clear Tourmaline

Chalcedony (Agate/Carnelian) (Cryptocrystalline Quartz (SiO2)) — mineral

Chalcedony (Agate/Carnelian)

Cryptocrystalline Quartz (SiO2)

Jasper (Microcrystalline Quartz (SiO2)) — sedimentary

Jasper

Microcrystalline Quartz (SiO2)

Granite Cobble (Granite) — igneous

Granite Cobble

Granite

Chert Pebble (Microcrystalline Quartz (SiO2)) — sedimentary

Chert Pebble

Microcrystalline Quartz (SiO2)

Carnelian (Carnelian (a variety of Chalcedony); SiO2 (Silicon Dioxide)) — mineral

Carnelian

Carnelian (a variety of Chalcedony); SiO2 (Silicon Dioxide)

Yellow Quartz (Citrine Quartz or Yellow Chalcedony) (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz (Citrine Quartz or Yellow Chalcedony)

Silicon Dioxide (SiO2)

Black Beach Pebble / Basalt Pebble (Basalt / Mafic Volcanic Rock) — igneous

Black Beach Pebble / Basalt Pebble

Basalt / Mafic Volcanic Rock

Jasper (Silicon dioxide (SiO2) with impurities) — sedimentary

Jasper

Silicon dioxide (SiO2) with impurities

Mixed rounded river pebbles (Polymictic alluvial gravel; likely quartz/quartzite, chert, and weathered feldspathic rocks) — sedimentary

Mixed rounded river pebbles

Polymictic alluvial gravel; likely quartz/quartzite, chert, and weathered feldspathic rocks

Rounded river pebble, likely basalt or fine-grained volcanic rock (Probable basalt (plagioclase–pyroxene ± olivine), though exact identification requires testing) — igneous

Rounded river pebble, likely basalt or fine-grained volcanic rock

Probable basalt (plagioclase–pyroxene ± olivine), though exact identification requires testing

Chert (River Siltstone/Quartzite type) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (River Siltstone/Quartzite type)

Microcrystalline Quartz (SiO2)

Banded Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert

Microcrystalline Quartz (SiO2)

Conglomerate (Conglomerate (Sedimentary rock)) — sedimentary

Conglomerate

Conglomerate (Sedimentary rock)

Jasper (Microcrystalline Quartz (SiO2)) — sedimentary

Jasper

Microcrystalline Quartz (SiO2)

Vesicular basalt (likely scoria) (Vesicular basalt; predominantly plagioclase, pyroxene, and possibly olivine) — igneous

Vesicular basalt (likely scoria)

Vesicular basalt; predominantly plagioclase, pyroxene, and possibly olivine

Jasper (Silicon Dioxide (SiO2) - Opaque Chalcedony) — sedimentary

Jasper

Silicon Dioxide (SiO2) - Opaque Chalcedony

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

Milky Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Citrine Quartz (Silicon Dioxide (SiO2) with trace Iron) — mineral

Citrine Quartz

Silicon Dioxide (SiO2) with trace Iron

Orbicular rhyolite (likely) (Silica-rich volcanic rock, chiefly quartz and feldspar with orbicular aggregates of feldspar, quartz, and mafic minerals) — igneous

Orbicular rhyolite (likely)

Silica-rich volcanic rock, chiefly quartz and feldspar with orbicular aggregates of feldspar, quartz, and mafic minerals

Polished brown river pebble (likely chert or fine-grained sandstone) (Indeterminate; probable microcrystalline quartz (chert) or quartz-rich sandstone) — sedimentary

Polished brown river pebble (likely chert or fine-grained sandstone)

Indeterminate; probable microcrystalline quartz (chert) or quartz-rich sandstone

Weathered iron-rich concretion or ironstone cobble (Limonite/goethite-rich ironstone, commonly with hematite and quartz) — sedimentary

Weathered iron-rich concretion or ironstone cobble

Limonite/goethite-rich ironstone, commonly with hematite and quartz

River Pebbles and Cobbles (Polymictic Gravel / Water-worn Lithic Fragments) — sedimentary

River Pebbles and Cobbles

Polymictic Gravel / Water-worn Lithic Fragments

Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble

Silicon Dioxide (SiO2)

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

Milky Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

River Rock (Granitic Gneiss) (Foliated Granitic Gneiss) — metamorphic

River Rock (Granitic Gneiss)

Foliated Granitic Gneiss

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

Sandstone (likely Quartzose Sandstone)

Arenite (composed primarily of SiO2)

Chert (Fossiliferous) (Chert (Cryptocrystalline Silica/SiO2)) — sedimentary

Chert (Fossiliferous)

Chert (Cryptocrystalline Silica/SiO2)

Gabbro (River Cobble) (Gabbro (mafic intrusive rock)) — igneous

Gabbro (River Cobble)

Gabbro (mafic intrusive rock)

Chert / Jasper (Silicon Dioxide (SiO2)) — sedimentary

Chert / Jasper

Silicon Dioxide (SiO2)

Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Banded Agate (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Banded Agate

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Rounded gray pebble (Unidentified lithic pebble; likely quartz-rich sandstone, quartzite, or fine-grained igneous rock) — sedimentary

Rounded gray pebble

Unidentified lithic pebble; likely quartz-rich sandstone, quartzite, or fine-grained igneous rock

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

Jasper

Silicon Dioxide (Microcrystalline Quartz, SiO2)

Yellow Quartz (Citrine or Quartzite Pebble) (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz (Citrine or Quartzite Pebble)

Silicon Dioxide (SiO2)

Jasper (Silicon dioxide (SiO2)) — sedimentary

Jasper

Silicon dioxide (SiO2)

Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble

Silicon Dioxide (SiO2)

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

Milky Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Yellow Quartz (Citrine/Yellow Jasper mix) (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz (Citrine/Yellow Jasper mix)

Silicon Dioxide (SiO2)

Basalt River Stone (Basalt) — igneous

Basalt River Stone

Basalt

Quartz Pebble (Beach Agate / Chalcedony Pebble) (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble (Beach Agate / Chalcedony Pebble)

Silicon Dioxide (SiO2)

Rounded quartz pebble (tentative) (Quartz, silicon dioxide (SiO₂)) — mineral

Rounded quartz pebble (tentative)

Quartz, silicon dioxide (SiO₂)