Gneiss (specifically a weathered Amphibolite or Garnet Gneiss)
Gneiss (complex silicate composition)
metamorphic
Category
Mineral, Often A Rock Given Its Aggregate Nature
Browse mineral, often a rock given its aggregate nature specimens identified by the Rock Identifier community.
Basalt
Basalt (Mafic volcanic rock)
igneous
Banded River Rock / Gneiss (highly weathered)
Gneiss
Metamorphic rock
Andesite
Andesite (Intermediate Volcanic Rock)
igneous
River Rock (Greywacke/Siltstone)
Siltstone / Argillaceous Greywacke
sedimentary
Scoria (Vesicular Basalt)
Scoria (Extrusive Igneous Rock)
igneous
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
sedimentary
Agate (Slab)
Agate (Cryptocrystalline variety of Quartz, SiO2)
Mineral
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
mineral
Green Quartzite (River Stone)
Metamorphic Quartz (SiO2) with inclusions (typically Fuchsite or Chlorite)
metamorphic
Chert (Jasper/Flint variation)
Chert (SiO2)
sedimentary
Basalt
Basalt
igneous
Granite
Granite (High-silica plutonic rock)
igneous
Turquoise (likely stabilized or Howlite/Magnesite imitation)
Hydrated phosphate of copper and aluminium, CuAl6(PO4)4(OH)8·4H2O
mineral
Quartz Conglomerate
Quartz Conglomerate (clastic sedimentary rock)
sedimentary
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
mineral
Granitic Gneiss
Gneiss (high-grade metamorphic rock primarily of quartz, feldspar, and mica)
metamorphic
Dyed Howlite (simulating Lavender/Purple Jade or Charoite)
Howlite: Ca2B5SiO9(OH)5 (when natural)
Mineral
Red Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary
Quartzite
Quartzite (primarily SiO2)
metamorphic
Basalt (Vesicular)
Mafic Volcanic Rock (rich in Magnesium and Iron)
Igneous
Basalt River Cobble
Basalt (Composition primarily Plagioclase Feldspar and Pyroxene)
igneous
Quartzite
Quartzite (SiO2)
metamorphic
Basalt
Mafic Igneous Rock (composed primarily of Pyroxene and Plagioclase Feldspar)
igneous
Jasper with Iron Staining
Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) impurities
sedimentary
Chert (with Quartz Veining)
Microcrystalline Quartz (SiO2)
sedimentary
Basalt
Basalt (Mafic volcanic rock)
igneous
River Cobble (likely Basalt)
Mafic Igneous Rock (Aphanitic)
Igneous
Banded Iron Formation
Banded Iron Formation (BIF)
Sedimentary Rock
Granite
Granite
igneous
Micaceous Rock (likely Muscovite Schist/Gneiss or a Muscovite-rich Specimen)
Predominantly Muscovite (KAl2(AlSi3O10)(F,OH)2), often found in rocks like Muscovite Schist or Muscovite Gneiss.
Metamorphic, Mineral (within a rock type)
Basalt
Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
igneous
Andesite
Intermediate Volcanic Rock (Andesite)
igneous
Lepidolite
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
mineral
Mica Schist
Mica Schist
metamorphic
Basalt
Basalt (Mafic volcanic rock)
igneous
Epidosite
Epidosite (Metasomatic rock consisting mainly of Epidote and Quartz)
metamorphic
Quartz (vein quartz)
SiO2 (Silicon Dioxide)
Mineral
Basalt (River Cobble)
Mafic Igneous Basalt (composed primarily of Plagioclase feldspar, Pyroxene, and Olivine)
Igneous
Terrazzo (Man-made Composite)
Cementitious or Resin-bound Lithic Composite
sedimentary (artificial)
Basalt
Mafic volcanic rock (Basalt)
igneous
Quartzite Pebble
Metamorphosed Quartz Sandstone (SiO2)
metamorphic