Gneiss
Gneiss (High-grade Metamorphic Rock)
Category
Browse mineral within a sedimentary rock specimens identified by the Rock Identifier community.
Gneiss
Gneiss (High-grade Metamorphic Rock)
Amethyst (Quartz)
Silicon Dioxide (SiO2) with iron impurities
Chert (varietal: Jasper or Ironstone nodule)
Microcrystalline Quartz (SiO2) with iron oxides
Glauconitic Sandstone
Glauconitic Sandstone (Greensand)
Chert (specifically Flint or Common Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Garnet-Mica Schist
Garnetiferous Porphyroblastic Schist
Ironstone Concretion (Limonite/Goethite)
Ferruginous Sandstone / Ironstone (FeO(OH)·nH2O)
Granite
Granite (composed primarily of Quartz SiO2, Alkali Feldspar KAlSi3O8, and Plagioclase Feldspar)
Jasper (Iron-stained Chert)
Silicon Dioxide (SiO2)
Basalt with Plagioclase Phenocrysts
Porphyritic Basalt
Granite
Phaneritic plutonic rock (primarily Quartz, Feldspar, and Mica)
Sandstone or Mudstone
Sedimentary Rock (Sandstone/Mudstone)
Banded Sandstone
Arenite (composed primarily of Quartz: SiO2)
Ferruginous Sandstone (Ironstone)
Sandstone with Hematite/Goethite cement (SiO2 + FeO(OH))
Red Sandstone (Old Red Sandstone Pebble)
Arenite with iron oxide (Fe2O3) cement
Red Sandstone
Arenite (Ferruginous Sandstone)
Limonite (Iron Ore/Sandstone mixture)
Limonite (FeO(OH)·nH2O) often mixed with Goethite and sedimentary matrix
Rose Quartz
Quartz (SiO₂), specifically a variety of Quartz
Asphalt Chunk (with aggregate)
Bituminous concrete / Anthropogenic conglomerate
Ferruginous Sandstone (with possible trace fossils)
Arenite with Iron-Oxide Cement (SiO2 with Fe2O3)
Gneiss
Gneiss (High-grade metamorphic rock composed primarily of Quartz, Feldspar, and various Micas)
Chert (Jasper variety)
Microcrystalline Quartz (SiO2)
Tree Agate
Dendritic Agate (Silicon Dioxide, SiO2)
Foliated Gneiss (River-Worn Pebble)
Gneiss (High-grade Regional Metamorphic Rock)
Chert (variations include Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Sandstone (Muddy/Silty Variety)
Arenite with high silt/clay content (clastic sedimentary rock)
Quartz Geode Fragment
Silicon Dioxide (SiO2)
Chert (often called Flint in this context)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Quartz (likely a form of massive or vein quartz)
Quartz (SiO₂)
Petrified Wood
Silicified Wood (primarily SiO2)
Vesicular Basalt (Scoria)
Mafic extrusive igneous rock (primarily Plagioclase Feldspar and Pyroxene)
Jasper with Quartz Druzy
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Gneiss (specifically a Banded Gneiss cobble)
Gneiss (composed mainly of Quartz, Feldspar, and Biotite/Amphibole)
Bumble Bee Jasper
Calcite-bearing Volcanic Tuff (not a true Jasper)
Chert (Flint nodule)
Silicon dioxide (SiO2)
Amethyst
Silicon Dioxide with Iron impurities (SiO2)
Gneiss
Gneiss (High-grade regional metamorphic rock)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Red Sandstone
Clastic Terrigenous Sedimentary Rock (typically Hematitic Quartz Arenite or Arkose)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)