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

Chert (Jasper/Flint variety)

Microcrystalline quartz (SiO2)

Quartz (Citrine or Iron-Stained variety) (Silicon Dioxide (SiO2)) — mineral

Quartz (Citrine or Iron-Stained variety)

Silicon Dioxide (SiO2)

River Stone (Chert/Siltstone) (Cryptocrystalline Quartz (SiO2) with trace impurities) — sedimentary

River Stone (Chert/Siltstone)

Cryptocrystalline Quartz (SiO2) with trace impurities

Chalcedony (Yellow Agate) (Cryptocrystalline Quartz (SiO2)) — mineral

Chalcedony (Yellow Agate)

Cryptocrystalline Quartz (SiO2)

Porphyry (Porphyritic Basalt or Porphyritic Andesite) — igneous

Porphyry

Porphyritic Basalt or Porphyritic Andesite

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

Chert (River Pebble)

Microcrystalline Quartz (SiO2)

Granite Pebble (Granite (Phaneritic intrusive igneous rock)) — igneous

Granite Pebble

Granite (Phaneritic intrusive igneous rock)

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

Milky Quartz Pebble

Silicon Dioxide (SiO2)

Granite Cobble/Pebble (Granite) — Igneous

Granite Cobble/Pebble

Granite

Quartzite (Quartzite (primarily SiO2)) — metamorphic

Quartzite

Quartzite (primarily SiO2)

Sandstone-based Concrete Fragment (Cementitious Composite with Sedimentary Aggregate) — sedimentary (man-made/anthropogenic)

Sandstone-based Concrete Fragment

Cementitious Composite with Sedimentary Aggregate

sedimentary (man-made/anthropogenic)

Quartz with Iron Staining (Silicon Dioxide (SiO2)) — mineral

Quartz with Iron Staining

Silicon Dioxide (SiO2)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble

Silicon Dioxide (SiO2)

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

Yellow Quartzite Pebble

Quartzite (primarily SiO2)

Milky Quartz (Silicon Dioxide (SiO2)) — Mineral

Milky Quartz

Silicon Dioxide (SiO2)

Granite (Granite (Felsic Intrusive Igneous Rock)) — igneous

Granite

Granite (Felsic Intrusive Igneous Rock)

Clear Quartz (Carved Dragon) (Quartz (Silicon Dioxide, SiO2)) — mineral

Clear Quartz (Carved Dragon)

Quartz (Silicon Dioxide, SiO2)

Metallic Ornament / Jewelry (N/A - This is an artificial object, not a geological specimen.) — This appears to be a man-made metallic object, likely jewelry, not a natural rock, mineral, or geological specimen.

Metallic Ornament / Jewelry

N/A - This is an artificial object, not a geological specimen.

This appears to be a man-made metallic object, likely jewelry, not a natural rock, mineral, or geological specimen.

Clear Quartz (Silicon Dioxide (SiO2)) — mineral

Clear Quartz

Silicon Dioxide (SiO2)

Chert (specifically Gray Chert) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Gray Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Quartz (Citrine or Iron-Stained) (Silicon Dioxide (SiO2)) — mineral

Quartz (Citrine or Iron-Stained)

Silicon Dioxide (SiO2)

Ironstone Concretion (Moqui Marble type) (Iron oxide concretion (Goethite/Hematite and Sandstone)) — sedimentary

Ironstone Concretion (Moqui Marble type)

Iron oxide concretion (Goethite/Hematite and Sandstone)

Basalt with Quartz Vein and Weathering Crust (Amygdaloidal or Porphyritic Basalt) — igneous

Basalt with Quartz Vein and Weathering Crust

Amygdaloidal or Porphyritic Basalt

Blue Sapphire (Corundum (Al2O3)) — mineral

Blue Sapphire

Corundum (Al2O3)

Limestone (Calcium Carbonate (primarily CaCO3 as Calcite or Aragonite)) — sedimentary

Limestone

Calcium Carbonate (primarily CaCO3 as Calcite or Aragonite)

Apache Tear (Obsidian) (Hydrated volcanic glass (SiO2 with inclusions)) — igneous

Apache Tear (Obsidian)

Hydrated volcanic glass (SiO2 with inclusions)

Chert (Chert Nodule with Chalky Cortex) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (Chert Nodule with Chalky Cortex)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Fluorite (Calcium Fluoride (CaF2)) — mineral

Fluorite

Calcium Fluoride (CaF2)

Chert (Field-collected specimen) (Chert (Crystalline Silica, SiO2)) — sedimentary

Chert (Field-collected specimen)

Chert (Crystalline Silica, SiO2)

Amygdaloidal Basalt (Amygdaloidal Basalt) — Igneous

Amygdaloidal Basalt

Amygdaloidal Basalt

Blue Lace Agate (Heat-treated/Crackle Quartz variety) (Silicon Dioxide (SiO2)) — mineral

Blue Lace Agate (Heat-treated/Crackle Quartz variety)

Silicon Dioxide (SiO2)

Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

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

Quartzite Pebble (River Rock)

Quartzite (SiO2)

Opal (Hydrous silicon dioxide (SiO2·nH2O)) — mineral

Opal

Hydrous silicon dioxide (SiO2·nH2O)

Granite (Felsic Plutonic Rock (Granite)) — igneous

Granite

Felsic Plutonic Rock (Granite)

Orthoclase Feldspar (Orthoclase (KAlSi3O8)) — Mineral

Orthoclase Feldspar

Orthoclase (KAlSi3O8)

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

Common Opal

Hydrated Silica (SiO2·nH2O)

Quartzite (Quartzite (primarily SiO2)) — metamorphic

Quartzite

Quartzite (primarily SiO2)

Diorite (River Pebble) (Phaneritic Intermediate Plutonic Rock (Diorite)) — igneous

Diorite (River Pebble)

Phaneritic Intermediate Plutonic Rock (Diorite)

Orange Quartzite / Carnelian Agate (Silicon Dioxide (SiO2)) — metamorphic

Orange Quartzite / Carnelian Agate

Silicon Dioxide (SiO2)

Granite Cobble (Granite (Felsic Plutonic Rock)) — igneous

Granite Cobble

Granite (Felsic Plutonic Rock)