Sandstone (likely Quartzose Sandstone pebble)
Arenite (primarily SiO2)
Category
Browse man made material (metal) specimens identified by the Rock Identifier community.
Sandstone (likely Quartzose Sandstone pebble)
Arenite (primarily SiO2)
Quartzite pebble
Quartzite (SiO2)
Quartzite
Quartzite (composed primarily of SiO2)
BROWN GRANITE (likely 'Tan Brown' or similar)
Granite (specifically a variety rich in orthoclase feldspar, often with biotite and possibly hornblende)
Limonite (Iron Ore)
Hydrous Iron Oxide (goethite, lepidocrocite)
Asphalt (Aggregate)
Bituminous macadam / Concrete Aggregate
Petrified Wood
Silicified wood (primarily SiO2 - Silicon Dioxide/Quartz)
Petrified Wood
Silicified Wood (SiO2)
Granite
Granite (a plutonic igneous rock composed primarily of quartz, feldspar, and mica)
Rhinestone (or glass crystal)
Silicon dioxide (if glass) / Various
Serpentinite (likely)
Serpentinite, dominated by serpentine-group minerals (antigorite, lizardite, chrysotile), commonly with magnetite and relic olivine/pyroxene
Possible weathered quartz-rich rock or iron-stained mineral fragment
Indeterminate; possibly quartz (SiO₂) with iron-oxide inclusions
Likely quartz-rich river pebble
Milky quartz or quartz-bearing granitic/gneissic fragment (SiO₂-dominant)
Jasper (likely red/brown jasper)
Microcrystalline quartz/chalcedony, SiO₂, colored mainly by iron oxides
Petrified Wood / Fossilized Wood
Silicified Wood (Silicon Dioxide - SiO2)
Diamond (or diamond simulant)
C
Jadeite (Jade)
NaAlSi2O6 (Sodium Aluminum Silicate)
Mottled gabbro or diorite pebble
Coarse-grained mafic/intermediate intrusive rock; chiefly plagioclase feldspar plus pyroxene, with possible amphibole or biotite
Granite or Pegmatite in host rock
Granitoid / Felsic Intrusive Rock
Petrified Wood (Silicified Fossil)
Silicified Wood (SiO2)
Milky quartz pebble
Quartz (silicon dioxide, SiO₂)
Diorite
Diorite (intermediate intrusive igneous rock)
Sandstone
Arenite (SiO2 based with mineral cement)
Chert (Quartz var.)
Silicon Dioxide (SiO2)
Sandstone
Arenite (Sedimentary rock comprising sand-sized grains)
Greenstone (Epidosite)
Epidosite (Metamorphosed Basalt/Diabase)
Milky Quartz
Quartz (SiO2)
Flint Pebble
Sedimentary cryptocrystalline quartz (SiO2)
Limestone
Calcium Carbonate (CaCO3)
Coquina
Biogenic Limestone (Calcite, CaCO3)
Diorite (Polished Tumble)
Diorite (Intermediate intrusive igneous rock)
Coquina
Biogenic Limestone (Calcium Carbonate, CaCO3)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Flint / Chert
Silicon dioxide (SiO2)
Micrometeorite (Spherule)
Extraterrestrial Accretion Spherule
Petrified Wood
Silicified Wood (SiO2)
Chert / Flint
Silicon dioxide (Microcrystalline Quartz, $SiO_2$)
Quartz (Chert/Flint variety)
Silicon Dioxide (SiO2)
Ruby in Zoisite (Anyolite) or possibly a dyed stone/agate
Anyolite (Ruby in green zoisite) or artificially altered chalcedony
Chondrite Meteorite
Stony Meteorite (Ordinary Chondrite)
Tumbled amethyst
Amethyst, purple quartz (SiO₂), colored by trace iron and irradiation
Sandstone (Ferruginous)
Arenite (with Iron Oxide)