Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Category
Browse igneous or sedimentary (water worn) specimens identified by the Rock Identifier community.
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Yellow Quartz (Citrine/Quartzite Pebble)
Silicon Dioxide (SiO2)
Quartz (Gravel fragment)
Quartz (Silicon Dioxide, SiO2)
White Quartz Pebble
Silicon Dioxide (SiO2)
Banded Gneiss
Gneiss (High-grade metamorphic rock typically composed of Quartz, Feldspar, and Mica)
Porphyry (specifically Porphyritic Rhyolite or Andesite)
Porphyritic Igneous Rock (composed of Phenocrysts in an Aphanitic groundmass)
Basalt with Epidote Veining
Basalt (Mafic Extrusive Rock) with Ca2(Al,Fe)3(SiO4)3(OH)
Diorite (Salt and Pepper Rock)
Diorite
Red Rhyolite Porphyry
Rhyolite (Porphyritic texture)
Diabase (Greenstone)
Diabase (Dolerite)
Granite
Granite
Nephrite Jade
Nephrite (a variety of the Calcium magnesium iron silicate mineral series Actinolite), Ca2(Mg, Fe)5Si8O22(OH)2
Red Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Hematite
Iron(III) oxide (Fe2O3)
Quartzite (River-worn Cobble)
Quartzite (composed primarily of SiO2)
Chert (Jasper variation)
Microcrystalline Quartz (SiO2)
Quartzite
Quartzite (primarily SiO2)
Dark Igneous Rock (Likely Basalt or Diabase)
Basalt (extrusive igneous rock) or Diabase (intrusive igneous rock - also known as Dolerite), largely composed of plagioclase feldspar, pyroxene (augite), and sometimes olivine and amphibole. Exact mineralogy would require thin section analysis.
Chert (Flint)
Chert (Microcrystalline Quartz, SiO2)
Amphibolite (specifically Hornblende Schist/Gneiss)
Amphibole-rich Metamorphic Rock
Quartz (Milky/Cloudy Variety)
Silicon Dioxide (SiO2)
Greenstone
Greenschist (commonly containing Chlorite, Actinolite, and Epidote)
Gneiss (High-grade Metamorphic Rock)
Gneiss (Metamorphic silicate rock)
Banded Gneiss
Gneiss (High-grade regional metamorphic rock)
Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Greenstone with Quartz Veining
Epidiorite or Metabasalt with SiO2 (Quartz) veins
Orange Quartzite (River Pebble)
Quartzite (primarily SiO2)
Chert (Smooth River Pebble)
Silicon Dioxide (SiO2)
Quartz (Iron-Stained)
Silicon Dioxide (SiO2)
Basalt Cobble
Aphanitic Mafic Igneous Rock (Basalt)
Gneiss (specifically a Banded Gneiss cobble)
Gneiss (composed mainly of Quartz, Feldspar, and Biotite/Amphibole)
Hematite (Tumbled)
Iron(III) oxide (Fe2O3)
Corundum (Sapphire variant)
Aluminium oxide (Al2O3)
Porphyry
Porphyritic Rhyolite or Andesite
Vesicular Basalt
Extrusive Mafic Igneous Rock (primarily Plagioclase Feldspar and Pyroxene)
Banded Jasper
Silicon Dioxide (SiO2) with iron oxide impurities
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Sandstone
Arenite
Granite
Granite (compositionally: Quartz, Feldspar, Mica)
Milky Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Quartzite Pebble
Quartzite (primarily SiO2)
Quartzite (River Cobble)
Quartzite (SiO2 silicon dioxide)