Rock Identifier

Category

Sedimentary (Formed From Silica Deposits)

Browse sedimentary (formed from silica deposits) specimens identified by the Rock Identifier community.

Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

Sandstone (Arenite (a specific type of sandstone with less than 15% matrix)) — Sedimentary rock

Sandstone

Arenite (a specific type of sandstone with less than 15% matrix)

Sedimentary rock

Shale (Shale (Lutite)) — sedimentary

Shale

Shale (Lutite)

Sandstone Pebble (Arenite (primarily Quartz, SiO2)) — sedimentary

Sandstone Pebble

Arenite (primarily Quartz, SiO2)

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Carnelian Agate (Silicon Dioxide with Iron Oxide impurities (SiO2)) — mineral

Carnelian Agate

Silicon Dioxide with Iron Oxide impurities (SiO2)

Septarian Nodule (Dragon Stone) (Septarian Geode (CaCO3 + Mg + Fe)) — sedimentary

Septarian Nodule (Dragon Stone)

Septarian Geode (CaCO3 + Mg + Fe)

Conglomerate (Clastic sedimentary rock (Conglomerate)) — sedimentary

Conglomerate

Clastic sedimentary rock (Conglomerate)

Chert (often called Flint or Jasper based on color) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often called Flint or Jasper based on color)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Amethyst (Silicon Dioxide (SiO2) with iron impurities) — Mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Sodalite (Sodalite (Na8(Al6Si6O24)Cl2)) — mineral

Sodalite

Sodalite (Na8(Al6Si6O24)Cl2)

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

Agate (Chalcedony Variation)

Silicon Dioxide (SiO2)

Sandstone (Ferruginous) (Arenite with Iron oxide staining (SiO2 with Fe2O3)) — sedimentary

Sandstone (Ferruginous)

Arenite with Iron oxide staining (SiO2 with Fe2O3)

Pebble (Likely Basalt or Siltstone) (Clastic sedimentary rock or mafic volcanic rock) — Igneous or Sedimentary

Pebble (Likely Basalt or Siltstone)

Clastic sedimentary rock or mafic volcanic rock

Igneous or Sedimentary

Red Jasper (Silicon Dioxide (SiO₂)) — Sedimentary Rock (Cryptocrystalline Quartz)

Red Jasper

Silicon Dioxide (SiO₂)

Sedimentary Rock (Cryptocrystalline Quartz)

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)

Emerald (Beryl (Be3Al2(SiO3)6) with Chromium and/or Vanadium impurities) — mineral

Emerald

Beryl (Be3Al2(SiO3)6) with Chromium and/or Vanadium impurities

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

White Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Quartz Pebble (with probable Iron staining) (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble (with probable Iron staining)

Silicon Dioxide (SiO2)

Orange Calcite (likely polished specimen) (Calcite) — Mineral

Orange Calcite (likely polished specimen)

Calcite

Quartzite (Quartzite (Primary mineral: Silicon Dioxide, SiO2)) — metamorphic

Quartzite

Quartzite (Primary mineral: Silicon Dioxide, SiO2)

Quartzite Cobble (Quartzite (primarily SiO2)) — metamorphic

Quartzite Cobble

Quartzite (primarily SiO2)

Quartz (Silicon Dioxide (SiO2)) — Mineral

Quartz

Silicon Dioxide (SiO2)

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

White Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Milky Quartz (Water-worn Pebble) (Silicon Dioxide (SiO2)) — mineral

Milky Quartz (Water-worn Pebble)

Silicon Dioxide (SiO2)

Tree Agate (Dendritic Agate (Silicon Dioxide, SiO2 + Manganese/Iron oxides)) — mineral

Tree Agate

Dendritic Agate (Silicon Dioxide, SiO2 + Manganese/Iron oxides)

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

Amethyst

Silicon Dioxide (SiO2) with Iron impurities

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

Precious Opal

Hydrated Silica (SiO2·nH2O)

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)

Limonite (often after Hematite or Goethite) (Limonite (FeO(OH)·nH2O)) — mineral

Limonite (often after Hematite or Goethite)

Limonite (FeO(OH)·nH2O)

Amethyst (Pale/Lavender variety) (Silicon Dioxide (SiO2)) — mineral

Amethyst (Pale/Lavender variety)

Silicon Dioxide (SiO2)

Septarian Nodule (Dragon Stone) (Septarian Concretion (CaCO3 with Siderite and Calcite)) — sedimentary

Septarian Nodule (Dragon Stone)

Septarian Concretion (CaCO3 with Siderite and Calcite)

Quartz Pebble (with Mica or Iron staining) (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble (with Mica or Iron staining)

Silicon Dioxide (SiO2)

Ocean Jasper (Orbicular Jasper) (Silicon Dioxide (SiO2)) — Sedimentary Rock

Ocean Jasper (Orbicular Jasper)

Silicon Dioxide (SiO2)

Sedimentary Rock

Black Onyx (Silicon Dioxide (SiO2)) — mineral

Black Onyx

Silicon Dioxide (SiO2)

Quartz (Water-worn pebble) (Silicon Dioxide (SiO2)) — mineral

Quartz (Water-worn pebble)

Silicon Dioxide (SiO2)

Sandstone (Sandstone (composed primarily of sand-sized minerals or rock grains)) — sedimentary

Sandstone

Sandstone (composed primarily of sand-sized minerals or rock grains)

Banded Agate (Pink/White) (Silicon Dioxide (SiO2) - Variety of Chalcedony) — mineral

Banded Agate (Pink/White)

Silicon Dioxide (SiO2) - Variety of Chalcedony

Milky Quartz (Water-Worn Cobble) (Silicon Dioxide (SiO2)) — mineral

Milky Quartz (Water-Worn Cobble)

Silicon Dioxide (SiO2)

Orange Calcite (Calcium Carbonate (CaCO3)) — mineral

Orange Calcite

Calcium Carbonate (CaCO3)

Ferruginous Quartz (Iron-stained Quartz) (Silicon Dioxide (SiO2) with Hematite/Limonite inclusions) — mineral

Ferruginous Quartz (Iron-stained Quartz)

Silicon Dioxide (SiO2) with Hematite/Limonite inclusions