Igneous And Metamorphic Derivative (Weathered)

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

Chert (Nodule)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

sedimentary

Milky Quartz

Silicon Dioxide (SiO2)

mineral

Chert (specifically Agate/Jasper variety)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

sedimentary

Jasper with Hematite inclusions

Silicon Dioxide (SiO2) with Ferric Oxide (Fe2O3)

sedimentary

Sandstone

Arenite (Siliclastic sedimentary rock)

sedimentary

Milky Quartz (Water-Worn Cobble)

Silicon Dioxide (SiO2)

mineral

Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

mineral

Milky Quartz with Limonite

Silicon Dioxide (SiO2)

mineral

Basalt

Igneous

Schist

Mica Schist (primarily Muscovite or Biotite sheet silicates)

metamorphic

Epidote in Granite Gneiss

Epidote bearing Orthogneiss (Ca2(Al,Fe)3(SiO4)3(OH))

metamorphic

Yellow Jasper

Jasper (Silicon Dioxide, SiO2)

sedimentary (or mineraloid)

Limestone

Calcium Carbonate (CaCO3)

sedimentary

Botryoidal Chalcedony (Agate/Carnelian)

Chalcedony (SiO2)

mineral

Sea Glass (White/Clear)

Amorphous Silica (Alkali-Lime-Silica Glass), SiO2 + Na2O + CaO

Anthropogenic (Man-made product subject to geological processes)

Chert (Nodule)

Silicon Dioxide (SiO2)

sedimentary

Greenstone with Quartz Veining

Epidiorite or Metabasalt with SiO2 (Quartz) veins

metamorphic

Greenstone

Protolith of basalt, diabase, or gabbro; often contains minerals like chlorite, actinolite, and epidote

metamorphic

Biotite (Mica)

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

mineral

Slag (Industrial Byproduct)

Ferrous/Non-ferrous Silicate

igneous (artificial/anthropogenic)

Basalt (Porphyritic)

Basalt (Mafic Extrusive Igneous Rock)

igneous

Botryoidal Goethite on Quartz

Goethite (α-Fe3+O(OH)) on Quartz (SiO2)

mineral

Banded Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

metamorphic

Quartz

Quartz (SiO₂)

Mineral

Banded Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

metamorphic

Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

metamorphic

Gneiss

Gneiss (High-grade regional metamorphic rock)

metamorphic

Aventurine (likely Green Aventurine)

Aventurine (a variety of quartz, SiO₂, with common inclusions of fuchsite)

Mineral/Metamorphic Rock

Gneiss (with Quartz and Mica)

Gneiss

metamorphic

Granite

Granite (Felsic intrusive igneous rock)

igneous

Garnet (Almandine or Spessartine likely)

Garnet Group Minerals (e.g., Almandine Fe3Al2(SiO4)3, Pyrope Mg3Al2(SiO4)3, Spessartine Mn3Al2(SiO4)3)

Mineral

Banded Metamorphic Rock (likely Quartzite or Serpentinite/Soapstone)

Metamorphic Rock (possibly a banded Quartzite or a foliated Serpentinite/Talc Schist based on appearance, general term for such a rock is 'Banded Metamorphic Rock' or 'Gneiss' if pronounced banding of different minerals)

Metamorphic

Banded Gneiss

Gneiss (Metamorphic high-grade rock)

metamorphic

Banded Gneiss

Gneiss (Metamorphic high-grade rock)

metamorphic

Jasper River Stone

Silicon Dioxide with Iron Oxide impurities (SiO2 + Fe2O3)

sedimentary

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

mineral

Blue Apatite

Fluorapatite / Chlorapatite [Ca5(PO4)3(F,Cl,OH)]

mineral

Milky Quartz (Quartz Vein)

Silicon Dioxide (SiO2)

mineral

Sunstone

Plagioclase Feldspar (specifically Oligoclase variety with hematite or goethite inclusions) Chemical Formula: (Ca,Na)(Al,Si)2Si2O8

Mineral

Garnet (Almandine/Pyrope)

Silicate Mineral (Group: X3Y2(SiO4)3 where X=Mg, Fe, Mn and Y=Al, Fe, Cr)

mineral

Clear Quartz Crystal

Quartz (Silicon Dioxide, SiO2)

mineral

Milky Quartz (with Iron staining)

Silicon Dioxide (SiO2)

mineral