Rock Identifier

Category

Igneous And Metamorphic Derivative (Weathered)

Browse igneous and metamorphic derivative (weathered) specimens identified by the Rock Identifier community.

Greenschist (Greenschist (comprising Actinolite, Chlorite, and Epidote)) — metamorphic

Greenschist

Greenschist (comprising Actinolite, Chlorite, and Epidote)

Banded Gneiss (Gneiss (High-grade Regional Metamorphic Rock)) — metamorphic

Banded Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Gneiss with Quartz Veining (Gneiss (High-grade regional metamorphic rock)) — metamorphic

Gneiss with Quartz Veining

Gneiss (High-grade regional metamorphic rock)

Greenstone (Greenschist facies) (Greenschist (composed primarily of Chlorite, Actinolite, and Epidote)) — metamorphic

Greenstone (Greenschist facies)

Greenschist (composed primarily of Chlorite, Actinolite, and Epidote)

Gneiss (with Quartz and Biotite Mica) (Gneiss) — metamorphic

Gneiss (with Quartz and Biotite Mica)

Gneiss

Gneiss (Gneiss) — metamorphic

Gneiss

Gneiss

Gneiss (Gneissic Metamorphic Rock (Mineral composition: Quartz, Feldspar, Amphibole/Biotite)) — metamorphic

Gneiss

Gneissic Metamorphic Rock (Mineral composition: Quartz, Feldspar, Amphibole/Biotite)

Weathered Volcanic Rock (possibly Rhyolite or Andesite Pebble) (Volcanic rock (e.g., Rhyolite or Andesite, specific identification would require thin section analysis or chemical assay). Mineral composition: Primarily feldspars (orthoclase and/or plagioclase), quartz (in rhyolite), micas, amphiboles, and sometimes pyroxenes.) — Igneous, specifically volcanic/extrusive (possibly Rhyolite or Andesite)

Weathered Volcanic Rock (possibly Rhyolite or Andesite Pebble)

Volcanic rock (e.g., Rhyolite or Andesite, specific identification would require thin section analysis or chemical assay). Mineral composition: Primarily feldspars (orthoclase and/or plagioclase), quartz (in rhyolite), micas, amphiboles, and sometimes pyroxenes.

Igneous, specifically volcanic/extrusive (possibly Rhyolite or Andesite)

Banded Gneiss (Gneiss (High-grade Regional Metamorphic Rock)) — metamorphic

Banded Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Banded Gneiss (Gneiss (High-grade regional metamorphic rock)) — metamorphic

Banded Gneiss

Gneiss (High-grade regional metamorphic rock)

Greenschist (Greenstone) (Greenschist) — metamorphic

Greenschist (Greenstone)

Greenschist

Calcite with iron staining (Calcium Carbonate (CaCO3)) — mineral

Calcite with iron staining

Calcium Carbonate (CaCO3)

Chert (White Chert / Flint) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (White Chert / Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Fossiliferous Limestone with Brachiopods (Calcium Carbonate (CaCO3) with fossilized Brachiopoda sp. (likely Order Spiriferida or Rhynchonellida)) — sedimentary

Fossiliferous Limestone with Brachiopods

Calcium Carbonate (CaCO3) with fossilized Brachiopoda sp. (likely Order Spiriferida or Rhynchonellida)

Chert Pebble / Brachiopod Fossil Internal Mold (Silicon Dioxide (SiO2) / Fossil: Brachiopoda (generic internal mold)) — sedimentary

Chert Pebble / Brachiopod Fossil Internal Mold

Silicon Dioxide (SiO2) / Fossil: Brachiopoda (generic internal mold)

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

Milky Quartz with Iron Staining

Quartz (Silicon Dioxide, SiO2)

Pyrite (Iron Disulfide (FeS2)) — mineral

Pyrite

Iron Disulfide (FeS2)

Rough Gemstone Grains (Mixed Sapphires and Quartz) (Corundum (Al2O3) and Quartz (SiO2)) — mineral

Rough Gemstone Grains (Mixed Sapphires and Quartz)

Corundum (Al2O3) and Quartz (SiO2)

Biotite Mica (Biotite (K(Mg,Fe)3AlSi3O10(OH,F)2)) — mineral

Biotite Mica

Biotite (K(Mg,Fe)3AlSi3O10(OH,F)2)

River Cobble (likely Basalt or Metagraywacke) (Non-specific water-worn lithic fragment) — igneous or metamorphic

River Cobble (likely Basalt or Metagraywacke)

Non-specific water-worn lithic fragment

igneous or metamorphic

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

Amethyst

Silicon Dioxide with Iron impurities (SiO2)

Amethyst (Polished/Carved Crystal) (Silicon Dioxide (SiO2) with trace Iron (Fe)) — mineral

Amethyst (Polished/Carved Crystal)

Silicon Dioxide (SiO2) with trace Iron (Fe)

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

Quartz (specifically Milky/White Quartz)

Silicon Dioxide (SiO2)

Feldspar (KAlSi3O8 - NaAlSi3O8 - CaAl2Si2O8) — mineral

Feldspar

KAlSi3O8 - NaAlSi3O8 - CaAl2Si2O8

Blue Sapphire (Corundum (Al2O3)) — mineral

Blue Sapphire

Corundum (Al2O3)

Biotite / Black Mica (Biotite K(Mg,Fe)3AlSi3O10(F,OH)2) — mineral

Biotite / Black Mica

Biotite K(Mg,Fe)3AlSi3O10(F,OH)2

Clear Quartz (Rock Crystal) (Silicon Dioxide (SiO2)) — mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

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

Smoky Quartz

Smoky Quartz (Silicon Dioxide, SiO2)

Clear Quartz (Silicon Dioxide (SiO2)) — mineral

Clear Quartz

Silicon Dioxide (SiO2)

Citrine Quartz (Silicon Dioxide (SiO2)) — mineral

Citrine Quartz

Silicon Dioxide (SiO2)

Clear Quartz (Crystalline Silicon Dioxide (SiO2)) — mineral

Clear Quartz

Crystalline Silicon Dioxide (SiO2)

Prasiolite (Silicon Dioxide (SiO2)) — mineral

Prasiolite

Silicon Dioxide (SiO2)

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

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

Quartz / Calcite Vein Rock (Silicon Dioxide (SiO2) or Calcium Carbonate (CaCO3)) — mineral

Quartz / Calcite Vein Rock

Silicon Dioxide (SiO2) or Calcium Carbonate (CaCO3)

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

Quartz (Milky/Rose variety)

Silicon Dioxide (SiO2)

Clear Quartz Crystal (Quartz (Silicon Dioxide, SiO2)) — mineral

Clear Quartz Crystal

Quartz (Silicon Dioxide, SiO2)

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Smoky Quartz (Silicon Dioxide (SiO2) with aluminum impurities) — mineral

Smoky Quartz

Silicon Dioxide (SiO2) with aluminum impurities

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Blue Sapphire (Corundum (Al2O3)) — mineral

Blue Sapphire

Corundum (Al2O3)

Hematite (Iron(III) oxide (Fe2O3)) — mineral

Hematite

Iron(III) oxide (Fe2O3)

Milky Quartz with Mica (Silicon Dioxide (SiO2) with Muscovite Mica [KAl2(AlSi3O10)(OH)2]) — mineral

Milky Quartz with Mica

Silicon Dioxide (SiO2) with Muscovite Mica [KAl2(AlSi3O10)(OH)2]