Rock Identifier

Category

Sedimentary Or Metamorphic (Base Substrate)

Browse sedimentary or metamorphic (base substrate) specimens identified by the Rock Identifier community.

Learn about Sedimentary Or Metamorphic (Base Substrate) in the encyclopedia

Sard

White Obsidian

Conglomerate

Quartzite Sandstone

Quartzite Sandstone

Metabasalt

Eulysite

Breccia

Hornfels

Ironstone

Anthracite

Metaquartzite

Slate

River Pebble (Gneiss or Quartzite variant) (Course-grained Metamorphic Rock (likely SiO2 dominant)) — metamorphic

River Pebble (Gneiss or Quartzite variant)

Course-grained Metamorphic Rock (likely SiO2 dominant)

Sandstone (Arenite) — sedimentary

Sandstone

Arenite

Quartz Pebble (Silicon Dioxide (SiO2)) — sedimentary

Quartz Pebble

Silicon Dioxide (SiO2)

River Pebble (Siltstone / Sandstone Pebble) (Sedimentary Rock (Quartz, Feldspar, Clay Minerals)) — sedimentary

River Pebble (Siltstone / Sandstone Pebble)

Sedimentary Rock (Quartz, Feldspar, Clay Minerals)

Fossiliferous Limestone (Coral Rag) (Biogenic Limestone (Calcium Carbonate, CaCO3)) — sedimentary

Fossiliferous Limestone (Coral Rag)

Biogenic Limestone (Calcium Carbonate, CaCO3)

Quartz pebble (Silicon dioxide (SiO2)) — sedimentary

Quartz pebble

Silicon dioxide (SiO2)

Expanded Clay Pebble (Lightweight Expanded Clay Aggregate (LECA)) — sedimentary

Expanded Clay Pebble

Lightweight Expanded Clay Aggregate (LECA)

Quartz Pebble (Silicon dioxide (SiO2)) — sedimentary

Quartz Pebble

Silicon dioxide (SiO2)

Yellow Quartzite River Pebbles (Metamorphic Silicon Dioxide (SiO2) with iron oxide inclusions) — metamorphic

Yellow Quartzite River Pebbles

Metamorphic Silicon Dioxide (SiO2) with iron oxide inclusions

Sapphire (Corundum (Al2O3)) — gemstone

Sapphire

Corundum (Al2O3)

Tumbled dark pebble (Indeterminate; likely basalt or fine-grained dark metamorphic rock) — mineral

Tumbled dark pebble

Indeterminate; likely basalt or fine-grained dark metamorphic rock

River Pebble / Chert Pebble (Microcrystalline Quartz (SiO2)) — sedimentary

River Pebble / Chert Pebble

Microcrystalline Quartz (SiO2)

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

White Quartz Pebble

Silicon Dioxide (SiO2)

Petoskey Stone (Hexagonaria percarinata (Fossilized Rugose Coral)) — sedimentary

Petoskey Stone

Hexagonaria percarinata (Fossilized Rugose Coral)

Moss-covered Rock Fragment (Weathered Rock Fragment with Epilithic Growth) — sedimentary

Moss-covered Rock Fragment

Weathered Rock Fragment with Epilithic Growth

River Stone (Basalt or Siltstone) (Mafic Volcanic Rock or Clastic Sedimentary Rock) — igneous or sedimentary

River Stone (Basalt or Siltstone)

Mafic Volcanic Rock or Clastic Sedimentary Rock

igneous or sedimentary

Jasper (SiO2) — Mineral

Jasper

SiO2

Jasper pebble (Silicon Dioxide (SiO2) with impurities) — sedimentary

Jasper pebble

Silicon Dioxide (SiO2) with impurities

Tufa (Calcareous Tufa (Calcium Carbonate, CaCO3)) — sedimentary

Tufa

Calcareous Tufa (Calcium Carbonate, CaCO3)

River Stone (Limestone) (Sedimentary Calcium Carbonate (CaCO3)) — sedimentary

River Stone (Limestone)

Sedimentary Calcium Carbonate (CaCO3)

Quartzite Pebble (Quartzite (SiO2)) — metamorphic

Quartzite Pebble

Quartzite (SiO2)

Quartzite Pebble (Metamorphosed Sandstone (SiO2)) — metamorphic

Quartzite Pebble

Metamorphosed Sandstone (SiO2)

Fossilized Bored Limestone (Limestone with Ichnofossils (Gastrochaenolites or Entobia)) — sedimentary

Fossilized Bored Limestone

Limestone with Ichnofossils (Gastrochaenolites or Entobia)

Quartzite Pebble (Quartzite (primarily SiO2)) — metamorphic

Quartzite Pebble

Quartzite (primarily SiO2)

Potassium-Rich Silicate Clay (inferred from biological context) (Phyllosilicate group (likely Illite or Smectite within surrounding soil substrate)) — mineral

Potassium-Rich Silicate Clay (inferred from biological context)

Phyllosilicate group (likely Illite or Smectite within surrounding soil substrate)

Mixed polished river pebbles, predominantly quartzite and quartz (Quartzite (SiO₂), quartz (SiO₂), with possible feldspar-rich and iron-stained lithologies) — metamorphic

Mixed polished river pebbles, predominantly quartzite and quartz

Quartzite (SiO₂), quartz (SiO₂), with possible feldspar-rich and iron-stained lithologies

White marble chips (Marble; predominantly calcite (CaCO₃)) — metamorphic

White marble chips

Marble; predominantly calcite (CaCO₃)

Aragonite (Sputnik habit) (Aragonite (Calcium Carbonate, CaCO3)) — mineral

Aragonite (Sputnik habit)

Aragonite (Calcium Carbonate, CaCO3)

White Buffalo Turquoise (or Howlite/Magnesite) (Calcite/Dolomite or Magnesite with Chert/Quartz inclusions) — gemstone

White Buffalo Turquoise (or Howlite/Magnesite)

Calcite/Dolomite or Magnesite with Chert/Quartz inclusions

River Stones (Basalt and Sedimentary Rock) (Basalt (dark specimen) and Siltstone/Mudstone (reddish specimen)) — igneous and sedimentary

River Stones (Basalt and Sedimentary Rock)

Basalt (dark specimen) and Siltstone/Mudstone (reddish specimen)

igneous and sedimentary

Druzy Quartz (Silicon Dioxide (SiO2)) — mineral

Druzy Quartz

Silicon Dioxide (SiO2)

Sandstone (River Pebble) (Clastic Sedimentary Rock (primarily Quartzite/Arenite)) — sedimentary

Sandstone (River Pebble)

Clastic Sedimentary Rock (primarily Quartzite/Arenite)

Black River Stone (Chert or Basalt Pebble) (Microcrystalline Quartz (SiO2) or Mafic Igneous Rock) — sedimentary

Black River Stone (Chert or Basalt Pebble)

Microcrystalline Quartz (SiO2) or Mafic Igneous Rock

Oolitic Limestone (Egg Stone) (Oolite (Chemical sedimentary rock, primarily CaCO3)) — sedimentary

Oolitic Limestone (Egg Stone)

Oolite (Chemical sedimentary rock, primarily CaCO3)

Tufa (Calcareous Tufa (CaCO3)) — sedimentary

Tufa

Calcareous Tufa (CaCO3)

Druzy Quartz (on Geode Fragment) (Silicon Dioxide (SiO2)) — mineral

Druzy Quartz (on Geode Fragment)

Silicon Dioxide (SiO2)

Rounded gray river cobble (Likely fine-grained sandstone, siltstone, or metamorphosed equivalent; exact identification requires a fresh surface and tests) — sedimentary

Rounded gray river cobble

Likely fine-grained sandstone, siltstone, or metamorphosed equivalent; exact identification requires a fresh surface and tests

Mixed beach gravel and cobbles (Polylithic alluvial or littoral clasts, including quartz, quartzite, chert, limestone, sandstone, and flint) — sedimentary

Mixed beach gravel and cobbles

Polylithic alluvial or littoral clasts, including quartz, quartzite, chert, limestone, sandstone, and flint

Sandstone Beach Pebble (Clastic Sandstone (SiO2 - Quartz-dominant)) — sedimentary

Sandstone Beach Pebble

Clastic Sandstone (SiO2 - Quartz-dominant)

Vesicular volcanic rock, likely pumice or scoria (Pumice/scoria; predominantly vesicular volcanic glass and feldspar-rich silicate minerals) — igneous

Vesicular volcanic rock, likely pumice or scoria

Pumice/scoria; predominantly vesicular volcanic glass and feldspar-rich silicate minerals

Blue sapphire (likely synthetic or treated corundum) (Corundum, aluminum oxide (Al₂O₃), blue from iron and titanium impurities) — gemstone

Blue sapphire (likely synthetic or treated corundum)

Corundum, aluminum oxide (Al₂O₃), blue from iron and titanium impurities

Quartzite River Stone (Metamorphic Quartzite (primarily SiO2)) — metamorphic

Quartzite River Stone

Metamorphic Quartzite (primarily SiO2)