Glauconitic Sandstone (or Greensand)
Glauconitic Siliciclastic Rock (Containing (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)
Category
Browse igneous rock (volcanic glass) specimens identified by the Rock Identifier community.
Glauconitic Sandstone (or Greensand)
Glauconitic Siliciclastic Rock (Containing (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)
Petrified Wood
Silicified Wood (SiO2)
Chert / Chalcedony (likely carnelian or flint variety)
Silicon Dioxide (SiO2)
Carnelian
Carnelian (subset of Chalcedony); SiO2 with Iron Oxide impurities
Banded Gneiss
Gneiss (High-grade metamorphic rock)
Jasper
Jasper (a variety of Chalcedony, SiO2)
Sandstone
Arenite (Sedimentary Rock)
Porphyritic Rhyolite (Red Rhyolite)
Rhyolite (Porphyry)
Quartz (Variety of Rough Mineral Specimens)
Silicon Dioxide (SiO2)
Iron Slag
Anthropogenic Vitreous Ferrous Silicate
Basalt with Iron Oxidation
Amygdaloidal Basalt (silicate rock primarily plagioclase, pyroxene, and olivine)
Amethyst (Tumbled Stone)
Amethyst (Silicon Dioxide with Iron impurities, SiO2)
Sulfide Ore (likely Galena and Sphalerite in Quartz)
Lead-Zinc Ore (PbS and ZnS)
Banded Agate (Tumbled)
Agate (Variety of Chalcedony/Quartz), SiO2
Red Jasper
Silicon Dioxide (SiO2) with Hematite inclusions
Carnelian
Carnelian (SiO2 - Chalcedony colored by Iron Oxide)
Gabbro
Gabbro (Mafic Plutonic Rock)
Quartz
Quartz (SiO2 - Silicon Dioxide)
Gneiss
High-grade Metamorphic Gneiss
Lapis Lazuli
Na8[Al6Si6O24]Sn (Lazurite-rich metamorphic rock)
Banded Agate (specifically Sardonyx)
Silicon Dioxide (SiO2) - variety of Chalcedony/Quartz
Chert
Silicon dioxide (SiO2)
Chert (potentially Flint or Mudstone)
Microcrystalline Quartz (SiO2)
Quartz (Chert/Chalcedony variety)
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Moss Agate
Chalcedony (Silicon Dioxide) with dendritic inclusions (SiO2)
Granodiorite
Phaneritic intrusive igneous rock (Granodiorite)
Granite
Phaneritic Plutonic Felsic Rock (major components: SiO2 and Al2O3)
Amethyst (Chevron Amethyst)
Amethystine Quartz (SiO2)
Granite
Plutonic felsic rock (Quartz, Feldspar, Mica)
Pink Granite
Phaneritic Felsic Igneous Rock (Rich in K-Feldspar)
Granitic Pegmatite
Granite Pegmatite (coarse-grained intrusive igneous rock)
Peridot
Olivine (Magnesium Iron Silicate - (Mg, Fe)2SiO4)
Quartz Geode Fragment
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Rose Quartz
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Jasper
Silicon dioxide (SiO2) with iron oxide inclusions
Slag Glass (Cullet)
Amorphous Silicon Dioxide (SiO2) with metal oxide colorants
Unakite
Unakite (Epidotized Granite)
Granite
Granite (composed mainly of Quartz, Feldspar, and Mica)
Granite
Granite (Felsic Plutonic Rock)