Basalt
Basalt (dominated by plagioclase feldspar and pyroxene)
Category
Browse organic (geological interest) specimens identified by the Rock Identifier community.
Basalt
Basalt (dominated by plagioclase feldspar and pyroxene)
Granite
Granite (Felsic intrusive igneous rock)
Banded Gneiss
Gneiss (pronounced 'nice')
Quartz (Druzy) in host rock
SiO₂ (Silicon Dioxide) as Quartz, with unspecified host rock components (likely silicates and iron oxides)
Chert (potentially Flint or Mudstone)
Microcrystalline Quartz (SiO2)
Granite
Granite (Mainly Quartz, Alkali Feldspar, and Plagioclase)
Chert (Jasper variation)
Silicon dioxide (SiO2)
Schist
Mica Schist (Medium-grade metamorphic rock)
Yellow Chert or Jasper
Silicon Dioxide (SiO2)
Yellow Calcite
Calcium Carbonate (CaCO3)
Rough Green Calcite
Calcite (Calcium Carbonate, CaCO3)
Banded Gneiss (River Rock/Pebble)
Gneiss (specifically a banded variety, likely a orthogneiss or paragneiss depending on parent rock)
Quartz (River Pebble)
Quartz (SiO₂ - Silicon Dioxide)
Quartz (likely Milky Quartz)
Quartz (SiO₂ - Silicon Dioxide)
Chert (specifically Gray Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Sandstone
Arenite or Sandstone
Orange Calcite
Calcium Carbonate (CaCO3)
Schist (Biotite Schist)
Biotite-bearing Schist (K(Mg,Fe)3AlSi3O10(F,OH)2)
Quartz / Chert
Silicon Dioxide (SiO2)
Granite
Phaneritic Felsic Igneous Rock (composed primarily of Quartz, Feldspar, and Mica)
Chert
Silicon dioxide (SiO2)
Granitic Pegmatite with Tourmaline and Sphalerite
Pegmatite containing Schorl (NaFe3Al6(BO3)3Si6O18(OH)4) and Sphalerite ((Zn,Fe)S)
Chert
Microcrystalline silica (SiO2)
Chert (Flint variety)
Silicon Dioxide (SiO2)
Granodiorite
Phaneritic Plutonic Rock - Granodiorite
Chert (specifically Flint or Jasper variant)
Microcrystalline quartz (SiO2)
Chert
Chert (Microcrystalline Quartz, SiO2)
Banded Chert
Microcrystalline Quartz (SiO2)
Chert (Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Orthoclase Feldspar
KAlSi3O8 (Potassium Aluminum Silicate)
Fossiliferous Limestone
Limestone (composed primarily of calcite with included fossils CaCO3)
Diorite
Phaneritic Intermediate Plutonic Rock (Diorite)
Yellow Quartzite
Silicon Dioxide (SiO2)
Granite
Granite (Alkali-feldspar granite)
Orange Calcite
Calcite (Calcium Carbonate - CaCO3)
Nephrite Jade
Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2), a variety of Actinolite-Tremolite
Granite
Granite (Felsic Plutonic Rock)
Chert (Flint)
Chert (Silicon Dioxide, SiO2)
Honey Calcite Sphere
Calcium Carbonate (CaCO3)
Orange Calcite
Calcium Carbonate (CaCO3)
Granite
Granite (a common rock type, not a single mineral; composed primarily of Quartz, Feldspar (Orthoclase and Plagioclase), and Mica (Biotite and/or Muscovite) and/or Amphibole)