Rock Identifier

Category

Mineralological Specimen

Browse mineralological specimen specimens identified by the Rock Identifier community.

Blue Lace Agate (Chalcedony (cryptocrystalline variety of Quartz), SiO2) — mineral

Blue Lace Agate

Chalcedony (cryptocrystalline variety of Quartz), SiO2

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

Amethyst

Silicon Dioxide with Iron impurities (SiO2)

Chert (Common Opal/Jasper variety) (Microcrystalline Quartz (SiO2) with hydration) — sedimentary

Chert (Common Opal/Jasper variety)

Microcrystalline Quartz (SiO2) with hydration

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

Quartz Pebble (Milky and Gray)

Quartz (Silicon Dioxide, SiO2)

Quartz with Iron Stains (Quartz (SiO2) with iron oxide/hydroxide staining) — Mineral

Quartz with Iron Stains

Quartz (SiO2) with iron oxide/hydroxide staining

Granodiorite Pebble (Granodiorite) — igneous

Granodiorite Pebble

Granodiorite

Basalt Beach Pebble (Basalt (Aphanitic Mafic Volcanic Rock)) — igneous

Basalt Beach Pebble

Basalt (Aphanitic Mafic Volcanic Rock)

Yellow Quartzite (River Pebble) (Quartzite (SiO2 with iron oxide impurities)) — metamorphic

Yellow Quartzite (River Pebble)

Quartzite (SiO2 with iron oxide impurities)

Basalt (Basalt (dominated by plagioclase feldspar and pyroxene)) — igneous

Basalt

Basalt (dominated by plagioclase feldspar and pyroxene)

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

Quartz (Common Quartz Pebble)

Silicon Dioxide (SiO2)

Basalt (River Rock pebble) (Basalt (a mafic extrusive igneous rock)) — igneous

Basalt (River Rock pebble)

Basalt (a mafic extrusive igneous rock)

Chert (Jasper/Common Opal mix) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper/Common Opal mix)

Microcrystalline Quartz (SiO2)

Quartzite with inclusions (Metamorphic Rock (Mainly SiO2)) — metamorphic

Quartzite with inclusions

Metamorphic Rock (Mainly SiO2)

Chert (Jasper-bearing) (Microcrystalline silica (SiO2) with iron oxide inclusions) — sedimentary

Chert (Jasper-bearing)

Microcrystalline silica (SiO2) with iron oxide inclusions

Sandstone Pebble (Arenite (primarily SiO2)) — sedimentary

Sandstone Pebble

Arenite (primarily SiO2)

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

Jasper (Red Chert)

Jasper (Silicon Dioxide, SiO2)

Dyed Quartzite (Metamorphosed Quartz (SiO2) with synthetic pigment) — metamorphic

Dyed Quartzite

Metamorphosed Quartz (SiO2) with synthetic pigment

Chert (Iron-stained) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Iron-stained)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Rhyolite Pebble (Rhyolite) — igneous

Rhyolite Pebble

Rhyolite

Banded Gneiss (Gneiss (complex metamorphic silicate rock)) — metamorphic

Banded Gneiss

Gneiss (complex metamorphic silicate rock)

Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble

Silicon Dioxide (SiO2)

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

Milky Quartz Pebble

Silicon Dioxide (SiO2)

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

Sandstone (likely Quartzose Sandstone)

Arenite (composed primarily of SiO2)

Gneiss (High-grade metamorphic rock (Gneiss)) — metamorphic

Gneiss

High-grade metamorphic rock (Gneiss)

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

Chert (Yellow Jasper variant)

Microcrystalline Quartz (SiO2)

Chert (Arrowhead/Tool variety) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Arrowhead/Tool variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Iron Slag (Iron Slag (Industrial Vitreous Material)) — Mineral/By-product

Iron Slag

Iron Slag (Industrial Vitreous Material)

Mineral/By-product

Quartz (Tumbled) (Silicon Dioxide (SiO2)) — mineral

Quartz (Tumbled)

Silicon Dioxide (SiO2)

Banded Chert (River Cobble) (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert (River Cobble)

Microcrystalline Quartz (SiO2)

Devil's Toenail (Fossil Oyster) (Gryphaea arcuata (Calcium Carbonate, CaCO3)) — sedimentary

Devil's Toenail (Fossil Oyster)

Gryphaea arcuata (Calcium Carbonate, CaCO3)

Rhyolitic Tuff (Rhyolitic Tuff / Pyroclastic rock) — igneous

Rhyolitic Tuff

Rhyolitic Tuff / Pyroclastic rock

Chert (often called Flint when dark or worked) (Cryptocrystalline silica (SiO2)) — sedimentary

Chert (often called Flint when dark or worked)

Cryptocrystalline silica (SiO2)

Yellow Quartzite Pebble (Quartzite (SiO2 with Iron Oxide staining)) — metamorphic

Yellow Quartzite Pebble

Quartzite (SiO2 with Iron Oxide staining)

Pink Granite (Phaneritic Felsic Igneous Rock (composed primarily of K-Feldspar, Quartz, and Plagioclase)) — igneous

Pink Granite

Phaneritic Felsic Igneous Rock (composed primarily of K-Feldspar, Quartz, and Plagioclase)

Petrified Wood (Silicified wood (Quartz/Chalcedony/Opal replacing organic matter)) — sedimentary

Petrified Wood

Silicified wood (Quartz/Chalcedony/Opal replacing organic matter)

Chert (Jasper/Flint variety) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (Jasper/Flint variety)

Microcrystalline quartz (SiO2)

Quartzite River Pebble (Quartzite (primarily SiO2)) — metamorphic

Quartzite River Pebble

Quartzite (primarily SiO2)

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

Chert (Jasper variety)

Silicon Dioxide (SiO2)

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

Granite Cobble

Plutonic Igneous Rock (Granitic)

Granite Pebble (Granite (composition of Quartz, Alkali Feldspar, and Plagioclase)) — igneous

Granite Pebble

Granite (composition of Quartz, Alkali Feldspar, and Plagioclase)

Dyed Agate (Silicon Dioxide (SiO2)) — mineral

Dyed Agate

Silicon Dioxide (SiO2)

Chert (Flint variety) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)