Rock Identifier

Category

Igneous Or Sedimentary (Water Worn)

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

Black River Stone (likely Basalt or Chert) (Basalt (primarily Plagioclase Feldspar and Pyroxene)) — igneous

Black River Stone (likely Basalt or Chert)

Basalt (primarily Plagioclase Feldspar and Pyroxene)

Chalcedony (Common Agate pebble) (Silicon Dioxide (SiO2)) — mineral

Chalcedony (Common Agate pebble)

Silicon Dioxide (SiO2)

Yellow Jasper (Jasper (SiO2) with iron hydroxide inclusions) — sedimentary

Yellow Jasper

Jasper (SiO2) with iron hydroxide inclusions

Hag Stone (Calcareous sedimentary rock (often Chert, Flint, or Limestone)) — sedimentary

Hag Stone

Calcareous sedimentary rock (often Chert, Flint, or Limestone)

Mixed Quartz and Jasper Pebbles (Silicon Dioxide (SiO2)) — Mineral

Mixed Quartz and Jasper Pebbles

Silicon Dioxide (SiO2)

Jasper (Silicon dioxide (SiO2)) — sedimentary

Jasper

Silicon dioxide (SiO2)

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

Milky Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Ferruginous Quartz Cobble (Silicon Dioxide (SiO2) with Iron Oxide inclusions) — mineral

Ferruginous Quartz Cobble

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Yellow Quartz (Citrine or Iron-Stained Quartz) (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz (Citrine or Iron-Stained Quartz)

Silicon Dioxide (SiO2)

Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble

Silicon Dioxide (SiO2)

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

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Opal (Hydrated Amorphous Silica (SiO2·nH2O)) — mineral

Opal

Hydrated Amorphous Silica (SiO2·nH2O)

Banded Gneiss (Gneiss (High-grade Regional Metamorphic Rock)) — metamorphic

Banded Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Foliated Gneiss (River-Worn Pebble) (Gneiss (High-grade Regional Metamorphic Rock)) — metamorphic

Foliated Gneiss (River-Worn Pebble)

Gneiss (High-grade Regional Metamorphic Rock)

Granite Pebble (Granite (Phaneritic intrusive igneous rock)) — igneous

Granite Pebble

Granite (Phaneritic intrusive igneous rock)

Chert (and/or River Pebble) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (and/or River Pebble)

Microcrystalline quartz (SiO2)

Sandstone (Quartzite-rich River Cobble) (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone (Quartzite-rich River Cobble)

Clastic sedimentary rock (primarily SiO2)

Chert (Polished River Pebble) (Chert (SiO2)) — sedimentary

Chert (Polished River Pebble)

Chert (SiO2)

Chert (Yellow Jasper variant) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Yellow Jasper variant)

Microcrystalline Quartz (SiO2)

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Jasper (Silicon dioxide (SiO2)) — sedimentary

Jasper

Silicon dioxide (SiO2)

Sandstone (with Iron Staining) (Clastic Sedimentary Rock (SiO2 with Fe2O3/FeO oxides)) — sedimentary

Sandstone (with Iron Staining)

Clastic Sedimentary Rock (SiO2 with Fe2O3/FeO oxides)

Granite Pebble (Phaneritic Felsic Igneous Rock) — igneous

Granite Pebble

Phaneritic Felsic Igneous Rock

Chert (Smooth River Pebble) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Smooth River Pebble)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Milky Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Sandstone (likely Siltstone) (Arenite or Siltstone (high SiO2 content)) — sedimentary

Sandstone (likely Siltstone)

Arenite or Siltstone (high SiO2 content)

Basalt (Aphanitic Mafic Igneous Rock) — igneous

Basalt

Aphanitic Mafic Igneous Rock

Quartz Vein in River Siltstone (Crystalline Quartz (SiO2) in Siliclastic Matrix) — sedimentary

Quartz Vein in River Siltstone

Crystalline Quartz (SiO2) in Siliclastic Matrix

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

Milky Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

River Stone (River Pebbles) (Alluvial Deposit (typically Quartzite, Sandstone, or Granite clasts)) — sedimentary

River Stone (River Pebbles)

Alluvial Deposit (typically Quartzite, Sandstone, or Granite clasts)

Sandstone (Arenite (SiO2 primarily)) — sedimentary

Sandstone

Arenite (SiO2 primarily)

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

Yellow Chalcedony (Agate)

Silicon Dioxide (SiO2)

Yellow Jasper (Silicon Dioxide (SiO2)) — sedimentary

Yellow Jasper

Silicon Dioxide (SiO2)

Andesite River Stones (Andesite) — igneous

Andesite River Stones

Andesite

Red Jasper (River Stone) (Jasper (Silicon Dioxide, SiO2 plus iron oxide inclusions)) — sedimentary

Red Jasper (River Stone)

Jasper (Silicon Dioxide, SiO2 plus iron oxide inclusions)

River Quartz (Milky and Smoky mix) (Silicon Dioxide (SiO2)) — mineral

River Quartz (Milky and Smoky mix)

Silicon Dioxide (SiO2)

Magnetite / Iron-Rich Concretion (Magnetite (Fe3O4) or Bog Iron Limonite) — mineral

Magnetite / Iron-Rich Concretion

Magnetite (Fe3O4) or Bog Iron Limonite

Porphyritic Rhyolite (Rhyolite (Porphyry)) — igneous

Porphyritic Rhyolite

Rhyolite (Porphyry)

Granite (Granite) — Igneous

Granite

Granite

Conglomerate (Clastic sedimentary conglomerate) — sedimentary

Conglomerate

Clastic sedimentary conglomerate

Basalt (Basalt) — igneous

Basalt

Basalt

Basalt (Basalt (composition of plagioclase feldspar and pyroxene)) — Igneous

Basalt

Basalt (composition of plagioclase feldspar and pyroxene)