Dark gray weathered pebble, likely basalt
Basalt; chiefly plagioclase feldspar, pyroxene, and commonly olivine or iron oxides
Category
Browse mixed: igneous and sedimentary specimens identified by the Rock Identifier community.
Dark gray weathered pebble, likely basalt
Basalt; chiefly plagioclase feldspar, pyroxene, and commonly olivine or iron oxides
Rounded river pebbles, likely basalt and sandstone/conglomerate
Probable basalt (dark specimen) and ferruginous sandstone or weathered conglomerate (tan specimen)
Unidentified weathered rock fragments
Likely mixed silicate rocks; specific identification requires testing
Red Jasper with Quartz Veining
Microcrystalline Quartz (SiO2)
Jasper and Quartz Breccia
Silica breccia (SiO2)
Fossiliferous limestone with silicified fossil material
Bioclastic limestone; likely marine mollusk/coral fragments, locally replaced by chalcedony or calcite
Mineral and Rock Collection (Assorted)
Mixed collection including Quartz (SiO2), Jasper (SiO2 with impurities), Rose Quartz, and Aventurine
General river rock or weathered cobble
Mixed rock composition
Weathered granitic rock fragment
Likely granite or granodiorite, composed mainly of quartz, feldspar, and mica
Gneiss
Gneiss (High-grade metamorphic rock composed primarily of Quartz, Feldspar, and various Micas)
Quartz with Mica inclusions (Pegmatite)
Silicon Dioxide (SiO2) with Muscovite/Biotite inclusions
Granite or Pegmatite with Quartz and Feldspar
Granitoid
Beach Pebbles and Jasper
Quartz / Microcrystalline Silicon Dioxide (SiO2)
Concrete fragment with Aggregate
Anthropogenic Concrete with Calcarious and Siliceous Aggregate
Mixed river stones and gravel
Polymictic alluvial clasts; individual pieces may include quartzite, granite, basalt, sandstone, limestone, and slate
Mixed stone-bead bracelet, likely agate/jasper and possibly sodalite or dyed quartz
Primarily microcrystalline quartz (SiO₂) varieties, with opaque iron-rich chalcedony/jasper and probable blue sodalite or dyed material
Weathered quartz-rich pebble
Likely quartz-rich granitoid (quartz and feldspar); exact identification is uncertain from the image
Weathered conglomeratic volcanic rock
Likely basaltic volcanic breccia or agglomerate, with plagioclase, pyroxene, volcanic glass, and lithic fragments
Mixed collection of quartz-rich rocks and minerals
Quartz (SiO₂), with some pieces possibly containing feldspar or mica; exact identification is uncertain from the image
Conglomeratic sandstone or breccia specimen
Quartz-rich clastic sedimentary rock; likely sandstone with pebble-sized quartz, feldspar, and lithic clasts
Mixed tumbled gravel and quartz-rich sandstone
Primarily quartz (SiO₂), feldspar, and lithic sedimentary fragments; one piece appears to be quartz-rich sandstone
Mixed collection of minerals and rocks (Jasper, Carnelian, Granite, and Quartz)
Silicon Dioxide (SiO2) with varying impurities for silicates and igneous aggregates
Soil with Mineral Detritus and Quartz Fragments
Regolith / Silicate Mineral Aggregate
Mahogany Obsidian
Volcanic Glass with Hematite/Magnetite inclusions (SiO2 + Fe2O3)
Mixed mineral and rock specimen collection
Mixed assemblage, visibly including quartz, chalcedony/agate, feldspar, mica, dark mafic rocks, and possibly calcite or gypsum
Sodalite
Na4Al3(SiO4)3Cl (Sodium Aluminum Silicate Chloride)
Pink Granite
Granite (Felsic Plutonic Rock)
Unidentified polished stone fragments
Indeterminate; likely mixed lapidary specimens, possibly jasper, agate, or quartz-bearing rock
Sodalite
Sodalite (Na8(Al6Si6O24)Cl2)
Unidentified gravel and stone fragments
Mixed, indeterminate lithologies; likely quartz, feldspar, and weathered silicate rock fragments
Crushed Stone (Gravel/Aggregates)
Crushed rock aggregate (varied composition including Granite, Limestone, and Quartz)
Mixed Mineral Collection (Quartz, Amethyst, Rose Quartz, Pyrite, etc.)
Mixed Silicates and Sulfides (SiO2, FeS2)
Sodalite
Sodalite (Na8Al6Si6O24Cl2)
Caribbean Calcite
Calcite (CaCO3) with Aragonite (CaCO3)
Tumbled beige stone, possibly quartz or calcite
Indeterminate from photograph; likely microcrystalline quartz (SiO₂) or calcite (CaCO₃)
Pink Granite
Phaneritic Felsic Intrusive Igneous Rock
Asphalt
Asphalt concrete
Ptygmatic Migmatite
Migmatite (consisting of Neosome and Paleosome fractions)
Copper Ore (Malachite and Limonite bearing)
Cuprite, Malachite, and Limonite mixture
Granite
Granite, a coarse-grained felsic intrusive igneous rock composed mainly of quartz, feldspar, and mica
Smoky Quartz and Orthoclase Feldspar
Granitic Pegmatite (SiO2 + KAlSi3O8)
Road-surface aggregate (crushed stone)
Unidentifiable mixed lithic aggregate; likely basaltic/andesitic fragments with feldspar, quartz, and weathered rock