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.

Moonstone (Orthoclase feldspar ((K,Na)AlSi3O8)) — mineral

Moonstone

Orthoclase feldspar ((K,Na)AlSi3O8)

Marble (Sculculpted) (Metamorphosed Limestone (primarily CaCO3)) — metamorphic

Marble (Sculculpted)

Metamorphosed Limestone (primarily CaCO3)

White Marble (Recrystallized Calcite (CaCO3)) — metamorphic

White Marble

Recrystallized Calcite (CaCO3)

Sandstone (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone

Clastic sedimentary rock (primarily SiO2)

Chert (Nodule) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Nodule)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Tree Agate (Dendritic Agate/Quartz) (Silicon Dioxide (SiO2) with trace Manganese or Iron oxide inclusions) — mineral

Tree Agate (Dendritic Agate/Quartz)

Silicon Dioxide (SiO2) with trace Manganese or Iron oxide inclusions

Note regarding image quality — Indeterminate

Note regarding image quality

Botryoidal Chalcedony (Silicon Dioxide (SiO2)) — mineral

Botryoidal Chalcedony

Silicon Dioxide (SiO2)

Tree Agate (Silicon Dioxide (SiO2) with dendritic inclusions) — mineral

Tree Agate

Silicon Dioxide (SiO2) with dendritic inclusions

Aragonite (Botryoidal/Coralloidal variety) (Aragonite (CaCO3)) — mineral

Aragonite (Botryoidal/Coralloidal variety)

Aragonite (CaCO3)

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)

Yellow Quartz (Citrine Quartz variety / Ferruginous Quartz) (Silicon Dioxide (SiO2) with iron inclusions) — mineral

Yellow Quartz (Citrine Quartz variety / Ferruginous Quartz)

Silicon Dioxide (SiO2) with iron inclusions

Milky Quartz with Iron Inclusions (Silicon Dioxide (SiO2)) — mineral

Milky Quartz with Iron Inclusions

Silicon Dioxide (SiO2)

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

Quartz Vein / Milky Quartz

Silicon Dioxide (SiO2)

Orthoclase (Potassium) Feldspar in Quartz (KAlSi3O8 (Potassium Aluminum Silicate)) — igneous

Orthoclase (Potassium) Feldspar in Quartz

KAlSi3O8 (Potassium Aluminum Silicate)

Yellow Calcite (Calcium Carbonate (CaCO3)) — mineral

Yellow Calcite

Calcium Carbonate (CaCO3)

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

Chalcedony (Agate Nodules)

Silicon Dioxide (SiO2)

Sandstone (clastic) (Clastic Sedimentary Rock (primarily composed of SiO2)) — sedimentary

Sandstone (clastic)

Clastic Sedimentary Rock (primarily composed of SiO2)

Gneiss (Metamorphic Rock) (Gneiss (high-grade regional metamorphic rock)) — metamorphic

Gneiss (Metamorphic Rock)

Gneiss (high-grade regional metamorphic rock)

Calcite (Calcite (Mineral; CaCO₃)) — Mineral

Calcite

Calcite (Mineral; CaCO₃)

Dendritic Agate (Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions) — mineral

Dendritic Agate

Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions

Banded Calcite (often marketed as Mexican Onyx or Onyx Marble) (Calcite (Calcium Carbonate, CaCO3)) — sedimentary

Banded Calcite (often marketed as Mexican Onyx or Onyx Marble)

Calcite (Calcium Carbonate, CaCO3)

Fluorite (Calcium Fluoride (CaF2)) — mineral

Fluorite

Calcium Fluoride (CaF2)

Quartzite (Quartzite (mostly SiO2)) — metamorphic

Quartzite

Quartzite (mostly SiO2)

Chert (Nodule) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Nodule)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Agate Geode / Nodular Chalcedony (Silicon Dioxide (SiO2) with impurities) — mineral

Agate Geode / Nodular Chalcedony

Silicon Dioxide (SiO2) with impurities

Quartzite (Quartzite (primarily SiO2)) — metamorphic

Quartzite

Quartzite (primarily SiO2)

Greywacke (River Pebble) (Greywacke sandstone with quartz veining) — sedimentary

Greywacke (River Pebble)

Greywacke sandstone with quartz veining

Lapis Lazuli (Lapis Lazuli (Metamorphic rock containing lazurite (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2, calcite, and pyrite)) — metamorphic

Lapis Lazuli

Lapis Lazuli (Metamorphic rock containing lazurite (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2, calcite, and pyrite)

Quartzite Pebble (Quartzite (principally SiO2)) — metamorphic

Quartzite Pebble

Quartzite (principally SiO2)

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Alexandrite in Matrix (Chrysoberyl (BeAl2O4 with Chromium impurities)) — mineral

Alexandrite in Matrix

Chrysoberyl (BeAl2O4 with Chromium impurities)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Yellow Quartz (Citrine/Gold Quartz) (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz (Citrine/Gold Quartz)

Silicon Dioxide (SiO2)

Lapis Lazuli (Lapis Lazuli (Complex silicate mixture containing Lazurite: (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)) — metamorphic

Lapis Lazuli

Lapis Lazuli (Complex silicate mixture containing Lazurite: (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)

Amethyst (Tumbled) (Silicon Dioxide (SiO2) with iron impurities) — mineral

Amethyst (Tumbled)

Silicon Dioxide (SiO2) with iron impurities

Iridescent Ammonite (Ammonoidea (Species: likely Cleoniceras or Desmoceras); Mineral: Aragonite/Ammolite (CaCO3)) — sedimentary (fossilized)

Iridescent Ammonite

Ammonoidea (Species: likely Cleoniceras or Desmoceras); Mineral: Aragonite/Ammolite (CaCO3)

sedimentary (fossilized)

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

Carnelian Agate

Silicon Dioxide (SiO2) with Iron Oxide impurities

Orange Calcite (Carved as a Horned Skull) (Calcium Carbonate (CaCO3)) — mineral

Orange Calcite (Carved as a Horned Skull)

Calcium Carbonate (CaCO3)

Limonite (Iron Ore/Sandstone mixture) (Limonite (FeO(OH)·nH2O) often mixed with Goethite and sedimentary matrix) — mineral

Limonite (Iron Ore/Sandstone mixture)

Limonite (FeO(OH)·nH2O) often mixed with Goethite and sedimentary matrix

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Chert (often called Flint or Jasper) (Silicon Dioxide (SiO2)) — sedimentary

Chert (often called Flint or Jasper)

Silicon Dioxide (SiO2)