Unakite
Epidotized Granite
Category
Browse metamorphic rock (primarily composed of minerals) specimens identified by the Rock Identifier community.
Unakite
Epidotized Granite
Quartzite
Quartzite (primarily SiO2)
Sandstone with Ironstone Concretion
Arenite with Hematite/Goethite nodules (Fe2O3 / FeO(OH))
Sandstone
Clastic sedimentary rock (primarily SiO2)
Banded Gneiss
Gneiss (pronounced "nice")
Green Kyanite
Kyanite (Al2SiO5)
Ferruginous Quartz
Quartz (Silicon Dioxide) - SiO2 with Iron Oxide inclusions
Blue Lace Agate
Cryptocrystalline Quartz (SiO2) with trace minerals
Fossilized Bone Fragment
Permineralized Vertebrate Fossil (Hydroxyapatite replaced by Minerals)
Muscovite Mica
Muscovite / KAl2(AlSi3O10)(OH)2
Shale with Vein Infillings
Shale (a fine-grained clastic sedimentary rock). The veins could be Calcite (CaCO3), Quartz (SiO2), or other minerals.
Banded Jasper (possibly "Picture Jasper")
Jasper (a microcrystalline variety of Quartz / Silicon Dioxide - SiO2)
Quartz
Quartz (SiO2 - Silicon Dioxide)
Quartzite River Rock
Quartzite (primarily SiO2)
Yellow Quartzite Pebble
Metamorphosed Quartz Sandstone (SiO2)
River Cobble (Quartzite)
Meta-orthoquartzite
Granitic Pegmatite
Granite (with coarse-grained Quartz, Feldspar, and Mica components)
Iolite-bearing Gneiss (Cordierite)
Cordierite (Mg2Al4Si5O18) in Gneiss matrix
Shale
Lutaceous Sedimentary Rock
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily SiO2 with Fe2O3 oxides)
Quartzite
Quartzite (primarily SiO2)
Nephrite Jade
Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)
Serpentine
Serpentine Group (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4
Petrified Wood
Silicified wood (primarily SiO2)
Olivine (often within Peridotite)
Magnesium iron silicate, (Mg,Fe)2SiO4
Dendritic Rhodonite
Rhodonite (Manganese Silicate), (Mn,Fe,Mg,Ca)SiO3
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic extrusive volcanic rock with secondary mineral infilling)
Quartz (likely tumbled or naturally water-worn)
Quartz (SiO₂ - Silicon Dioxide)
Quartzite River Rock
Quartzite (SiO2)
Diamond
C (Carbon)
Dendritic Agate
Chalcedony (SiO2) with manganese/iron oxide inclusions
Green Slag Glass
Cullet (Amorphous Silicon Dioxide with impurities)
Chakra Tumbled Stone Set
Various (including Amethyst [SiO2], Sodalite [Na8(Al6Si6O24)Cl2], Green Aventurine [SiO2], Red Jasper [SiO2], etc.)
Coquina / Fossiliferous Limestone
Calcite-rich Bioclastic Sedimentary Rock (CaCO3)
Amygdaloidal Basalt with Zeolite/Quartz Infill
Amygdaloidal Basalt (Host: (Mg,Fe)2SiO4 / CaAl2Si2O8; Infill: SiO2 or Na2Al2Si3O10·2H2O)
Red Sandstone Pebble
Arenite (primarily Quartz SiO2 with Hematite Fe2O3 staining)
Tiger Iron / Banded Iron Formation
Banded Iron Formation (SiO2 with Fe2O3 and FeOOH)
Quartz / Quartzite
Silicon Dioxide (SiO2)
Sandstone (with Manganese staining)
Arenite (composed primarily of SiO2)
Basalt with Weathering Crust
Extrusive mafic volcanic rock
Jasper River Stone
Silicon Dioxide with Iron Oxide impurities (SiO2 + Fe2O3)