Rock Identifier

Category

Sedimentary (Secondary Mineral Formation)

Browse sedimentary (secondary mineral formation) specimens identified by the Rock Identifier community.

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

Milky Quartz

Quartz (Silica / Silicon Dioxide, SiO2)

Red Jasper (Jasper (Silicon Dioxide with Iron Oxide impurities), SiO2) — mineral

Red Jasper

Jasper (Silicon Dioxide with Iron Oxide impurities), SiO2

Siltstone/Sandstone (possibly Wonderstone or Picture Sandstone) (Clastic Sedimentary Rock (primarily SiO2 with Iron Oxide inclusions)) — Sedimentary

Siltstone/Sandstone (possibly Wonderstone or Picture Sandstone)

Clastic Sedimentary Rock (primarily SiO2 with Iron Oxide inclusions)

Bog Iron / Limonite Concretion (Goethite/Limonite mixture (FeO(OH)·nH2O)) — sedimentary

Bog Iron / Limonite Concretion

Goethite/Limonite mixture (FeO(OH)·nH2O)

Amygdaloidal Basalt (Amygdaloidal Basalt (Mafic Extrusive volcanic rock)) — igneous

Amygdaloidal Basalt

Amygdaloidal Basalt (Mafic Extrusive volcanic rock)

Quartz Geode (Silicon Dioxide (SiO2)) — sedimentary

Quartz Geode

Silicon Dioxide (SiO2)

Amygdaloidal Basalt (Amygdaloidal Basalt (Mafic Volcanic Rock)) — igneous

Amygdaloidal Basalt

Amygdaloidal Basalt (Mafic Volcanic Rock)

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

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Banded Agate (White Agate) (Chalcedony (Silicon Dioxide, SiO2)) — mineral

Banded Agate (White Agate)

Chalcedony (Silicon Dioxide, SiO2)

Chert (specifically Iron-stained River Cobble) (Silicon Dioxide (SiO2)) — sedimentary

Chert (specifically Iron-stained River Cobble)

Silicon Dioxide (SiO2)

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

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Chert (Microcrystalline silica (SiO2)) — sedimentary

Chert

Microcrystalline silica (SiO2)

Quartz (Pebble) (Quartz (SiO₂)) — Mineral

Quartz (Pebble)

Quartz (SiO₂)

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

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Blue Calcite (Calcium Carbonate (CaCO3)) — mineral

Blue Calcite

Calcium Carbonate (CaCO3)

Red Jasper (Silicon Dioxide (SiO2) with iron oxide inclusions) — mineral

Red Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

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

Carnelian

Carnelian (SiO2, Silicon Dioxide with Iron Oxide impurities)

Blue Lace Agate (Geode/Druzy variant) (Chalcedony (SiO2) with Quartz druzy) — mineral

Blue Lace Agate (Geode/Druzy variant)

Chalcedony (SiO2) with Quartz druzy

Quartz (Milky or Cloudy Quartz) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky or Cloudy Quartz)

Silicon Dioxide (SiO2)

Chert (varietal: Jasper or Flint likely, but definitive identification is difficult from image) (SiO₂ (silicon dioxide)) — Sedimentary

Chert (varietal: Jasper or Flint likely, but definitive identification is difficult from image)

SiO₂ (silicon dioxide)

River Cobble (Salt and Pepper Gneiss) (Gneiss (High-grade regional metamorphic rock)) — metamorphic

River Cobble (Salt and Pepper Gneiss)

Gneiss (High-grade regional metamorphic rock)

Banded Agate (Cryptocrystalline Quartz (SiO2)) — mineral

Banded Agate

Cryptocrystalline Quartz (SiO2)

Limestone with Calcite Crystals (Calcium Carbonate (CaCO3)) — sedimentary

Limestone with Calcite Crystals

Calcium Carbonate (CaCO3)

Gneiss (Gneiss) — metamorphic

Gneiss

Gneiss

Copper-bearing Quartz (likely Chrysocolla or Malachite staining) (Cuprite, Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O) or Malachite staining on Quartz/Host Rock) — mineral

Copper-bearing Quartz (likely Chrysocolla or Malachite staining)

Cuprite, Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O) or Malachite staining on Quartz/Host Rock

Agate (specifically Botswana or Lake Superior style chalcedony) (Silicon Dioxide (SiO2)) — mineral

Agate (specifically Botswana or Lake Superior style chalcedony)

Silicon Dioxide (SiO2)

Blue Sapphire (Corundum (Al2O3)) — mineral

Blue Sapphire

Corundum (Al2O3)

Chalcedony (Chalcedony (a microcrystalline variety of Quartz, SiO2)) — Mineral

Chalcedony

Chalcedony (a microcrystalline variety of Quartz, SiO2)

Agate (Agate (a cryptocrystalline variety of Quartz, SiO₂)) — Mineral

Agate

Agate (a cryptocrystalline variety of Quartz, SiO₂)

Banded Gneiss (Gneiss (quartz-feldspar-biotite metamorphic rock)) — metamorphic

Banded Gneiss

Gneiss (quartz-feldspar-biotite metamorphic rock)

Peridot (Olivine (Magnesium Iron Silicate), (Mg, Fe)2SiO4) — mineral

Peridot

Olivine (Magnesium Iron Silicate), (Mg, Fe)2SiO4

Red Mudstone (Siltstone) (Lutite (primarily Quartz and Clay minerals with Hematite)) — sedimentary

Red Mudstone (Siltstone)

Lutite (primarily Quartz and Clay minerals with Hematite)

Amygdaloidal Basalt (Amygdaloidal Basalt (Ca-rich Plagioclase, Pyroxene, and Olivine)) — igneous

Amygdaloidal Basalt

Amygdaloidal Basalt (Ca-rich Plagioclase, Pyroxene, and Olivine)

Limonite with Opal infusion (FeO(OH)·nH2O (Limonite) / SiO2·nH2O (Opal)) — mineral

Limonite with Opal infusion

FeO(OH)·nH2O (Limonite) / SiO2·nH2O (Opal)

Vesicular Basalt (River Pebble) (Vesicular Basalt) — igneous

Vesicular Basalt (River Pebble)

Vesicular Basalt

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Amygdaloidal Basalt (Amygdaloidal Basalt (Mafic volcanic rock with secondary mineral fillings)) — igneous

Amygdaloidal Basalt

Amygdaloidal Basalt (Mafic volcanic rock with secondary mineral fillings)

Nuummite (Nuummite (Orthoamphibole rock / Anthophyllite-Gedrite blend)) — metamorphic

Nuummite

Nuummite (Orthoamphibole rock / Anthophyllite-Gedrite blend)

Banded Agate (Carnelian type) (Agate (Cryptocrystalline Quartz, SiO2)) — mineral

Banded Agate (Carnelian type)

Agate (Cryptocrystalline Quartz, SiO2)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Quartz (Sea Glass or River-worn Pebble style) (Silicon Dioxide (SiO2)) — mineral

Quartz (Sea Glass or River-worn Pebble style)

Silicon Dioxide (SiO2)

Gold Nugget (Native Gold (Au)) — mineral

Gold Nugget

Native Gold (Au)