Rock Identifier

Category

The Purple Specimen Is A Mineral (Amethyst); The White Specimen Is A Sedimentary Rock (Limestone Or Marble).

Browse the purple specimen is a mineral (amethyst); the white specimen is a sedimentary rock (limestone or marble). specimens identified by the Rock Identifier community.

Chert (River Stone) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (River Stone)

Microcrystalline Quartz (SiO2)

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

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Amethyst (as seen in jewelry) (Silicon Dioxide (SiO2) with iron impurities) — mineral

Amethyst (as seen in jewelry)

Silicon Dioxide (SiO2) with iron impurities

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

Sandstone

Arenite (composed primarily of SiO2)

Quartz (Milky/Chalcedony variety) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky/Chalcedony variety)

Silicon Dioxide (SiO2)

Basalt (Water-worn pebble) (Basalt (Mafic Extrusive Rock)) — igneous

Basalt (Water-worn pebble)

Basalt (Mafic Extrusive Rock)

Sandstone (Red Sandstone / River Stone) (Arenite (composed primarily of Quartz, SiO2, with Iron Oxide cementation)) — sedimentary

Sandstone (Red Sandstone / River Stone)

Arenite (composed primarily of Quartz, SiO2, with Iron Oxide cementation)

Quartzite Pebble (Quartzite (SiO2)) — metamorphic

Quartzite Pebble

Quartzite (SiO2)

Granite (Dioritic or Hornblende-rich) (Phaneritic Plutonic Felsic to Intermediate Igneous Rock) — igneous

Granite (Dioritic or Hornblende-rich)

Phaneritic Plutonic Felsic to Intermediate Igneous Rock

Chert (Polished Gemstone / River Stone) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Polished Gemstone / River Stone)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Banded Agate (specifically Sardonyx Agate) (Silicon Dioxide (SiO2) - Chalcedony variety) — mineral

Banded Agate (specifically Sardonyx Agate)

Silicon Dioxide (SiO2) - Chalcedony variety

Green Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Green Chert

Microcrystalline Quartz (SiO2)

Carnelian (Carnelian (Silicon Dioxide - SiO2)) — mineral

Carnelian

Carnelian (Silicon Dioxide - SiO2)

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

River Quartz (Milky and Smoky mix)

Silicon Dioxide (SiO2)

Yellow Quartz (Citrine-colored Quartz) (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz (Citrine-colored Quartz)

Silicon Dioxide (SiO2)

Fluorite (Fluorite (Calcium Fluoride - CaF2)) — mineral

Fluorite

Fluorite (Calcium Fluoride - CaF2)

Epidote with Quartz and Feldspar (Ca2(Al2,Fe3+)(SiO4)3(OH) (Epidote complex)) — metamorphic

Epidote with Quartz and Feldspar

Ca2(Al2,Fe3+)(SiO4)3(OH) (Epidote complex)

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

Chert (Jasper)

Microcrystalline Quartz (SiO2)

Chert (containing fossil leaf impression) (Microcrystalline silicon dioxide (SiO2)) — sedimentary

Chert (containing fossil leaf impression)

Microcrystalline silicon dioxide (SiO2)

Chert Pebble (Jasperoid/Flint) (Silicon Dioxide (SiO2) - cryptocrystalline quartz) — Sedimentary

Chert Pebble (Jasperoid/Flint)

Silicon Dioxide (SiO2) - cryptocrystalline quartz

Fluorite (Calcium Fluoride (CaF2)) — mineral

Fluorite

Calcium Fluoride (CaF2)

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

Quartz (Citrine)

Silicon Dioxide (SiO2)

Sandstone (Clastic Sedimentary Rock (composed mostly of SiO2)) — sedimentary

Sandstone

Clastic Sedimentary Rock (composed mostly of SiO2)

Chert (and Flint variant) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (and Flint variant)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Amygdaloidal Basalt (Basalt with secondary mineral infilling (commonly Zeolite, Calcite, or Quartz)) — igneous

Amygdaloidal Basalt

Basalt with secondary mineral infilling (commonly Zeolite, Calcite, or Quartz)

Chert or Flint (polished/water-worn) (Chert (a microcrystalline or cryptocrystalline variety of quartz, SiO2). Flint is a specific variety of chert.) — Sedimentary (most likely, as Chert is a sedimentary rock often found as nodules in limestone or as bedded deposits; however, it can also form by metasomatic replacement, which leans towards metamorphic processes under certain conditions)

Chert or Flint (polished/water-worn)

Chert (a microcrystalline or cryptocrystalline variety of quartz, SiO2). Flint is a specific variety of chert.

Sedimentary (most likely, as Chert is a sedimentary rock often found as nodules in limestone or as bedded deposits; however, it can also form by metasomatic replacement, which leans towards metamorphic processes under certain conditions)

Chalcedony with Druzy Quartz Geode (Silicon Dioxide (SiO2)) — mineral

Chalcedony with Druzy Quartz Geode

Silicon Dioxide (SiO2)

Quartz Vein in Metamorphic Rock (Silicon Dioxide (SiO2) within Metasedimentary host) — metamorphic

Quartz Vein in Metamorphic Rock

Silicon Dioxide (SiO2) within Metasedimentary host

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

Sandstone

Arenite (composed primarily of SiO2)

Banded Agate (Onyx type) (Silicon Dioxide (SiO2) - Cryptocrystalline Quartz) — mineral

Banded Agate (Onyx type)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

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

Sandstone (Quartzite-rich River Cobble)

Clastic sedimentary rock (primarily SiO2)

Yellow Chert (River Stone/Pebble) (Chert (Cryptocrystalline Quartz, SiO2)) — sedimentary

Yellow Chert (River Stone/Pebble)

Chert (Cryptocrystalline Quartz, SiO2)

Porphyritic Basalt (Drill Core) (Porphyritic Basalt with Plagioclase Phenocrysts) — igneous

Porphyritic Basalt (Drill Core)

Porphyritic Basalt with Plagioclase Phenocrysts

Banded Calcite (often sold as Caribbean Calcite or Mexican Onyx) (Calcium Carbonate (CaCO3)) — mineral

Banded Calcite (often sold as Caribbean Calcite or Mexican Onyx)

Calcium Carbonate (CaCO3)

Yellow Chalcedony (Silicon Dioxide (SiO2)) — mineral

Yellow Chalcedony

Silicon Dioxide (SiO2)

Banded Agate (Silicon Dioxide (SiO2)) — mineral

Banded Agate

Silicon Dioxide (SiO2)

Quartz (Crystal Cluster) (Silicon Dioxide (SiO2)) — mineral

Quartz (Crystal Cluster)

Silicon Dioxide (SiO2)

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

Chert (often called Flint or Jasper)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Druzy Quartz on Ironstone (Silicon Dioxide (SiO2) on Limonitic Ironstone) — mineral

Druzy Quartz on Ironstone

Silicon Dioxide (SiO2) on Limonitic Ironstone

Quartz (Milky/Clear Quartz) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky/Clear Quartz)

Silicon Dioxide (SiO2)

Clear Quartz (Silicon Dioxide (SiO2)) — mineral

Clear Quartz

Silicon Dioxide (SiO2)

Greenish rock with white veins, possibly epidote or chlorite bearing rock with quartz/calcite veins (Altered mafic rock or Epidosite) — metamorphic or igneous alteration

Greenish rock with white veins, possibly epidote or chlorite bearing rock with quartz/calcite veins

Altered mafic rock or Epidosite

metamorphic or igneous alteration