Diamond
Native Carbon (C)
Category
Browse man made glass (not a natural rock or mineral) specimens identified by the Rock Identifier community.
Diamond
Native Carbon (C)
Granite
Granite
Quartz Geode/Cluster
Quartz (SiO2)
Halite
Sodium Chloride (NaCl)
Turquoise
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Black Obsidian
Volcanic Glass (SiO2 + impurities)
Grey Quartzite Pebble
Quartzite (primarily SiO2)
Granodiorite
Granodiorite (containing Quartz, Plagioclase Feldspar, Biotite, and Hornblende)
Quartzite
Quartzite (Primary mineral: SiO2)
Quartz
Silicon Dioxide (SiO2)
Limonite (after Pyrite Pseudomorph)
Limonite (Hydrated Iron Oxide Mixture, FeO(OH)·nH2O)
Red Dyed Howlite
Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)
Amethyst
SiO2 (Silicon Dioxide) with Iron (Fe3+) impurities
Quartzite
Quartzite (SiO2)
River/Stream Pebble
Clast / Detrital Grain / Rounded Sedimentary Particle (Compositionally variable, commonly Quartz, Feldspar, Chert, or other resistant rock fragments)
Quartz (specifically Clear Quartz or Rock Crystal)
Silicon Dioxide (SiO2)
Quartz (in matrix)
Quartz (SiO₂)
Druzy Quartz Geode (Oco or Moroccan variety)
Silicon Dioxide (SiO2)
Desert Varnish on Sandstone
Ferromanganese coating on Quartz Arenite
Banded Gneiss (River Rock/Pebble)
Gneiss (specifically a banded variety often found as a river rock)
Emerald
Beryl (Be3Al2(SiO3)6) with Chromium/Vanadium impurities
Quartzite
Metamorphosed Quartz Sandstone (SiO2)
Chert Breccia (Yellow Jasper)
Silicon Dioxide (SiO2) - Brecciated Chert
Chert / Flint
Microcrystalline or cryptocrystalline quartz (SiO2)
Blue Apatite
Fluorapatite / Chlorapatite [Ca5(PO4)3(F,Cl,OH)]
Quartzite Pebbles (River Stones)
Quartzite (primarily Silicon Dioxide, SiO2)
Chert (varietal Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Banded Sandstone (Liesegang Rings)
Sedimentary Arenite (SiO2 with FeO/Fe2O3 impurities)
Diamond
Diamond (Pure Carbon - C)
Diamond (Faceted)
Carbon (C) - Diamond
Chevron Amethyst
Silicon Dioxide (SiO2) with iron impurities
Pearl (Biogenic Mineral)
Calcium Carbonate (primarily Aragonite) with Conchiolin; CaCO3
Howlite
Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)
Dream Amethyst (Chevron Amethyst)
Silicon Dioxide with inclusions (SiO2)
Rough Diamond
Diamond (pure carbon / C)
Dragon Vein Agate
Chalcedony (cryptocrystalline silica, SiO2) variety Agate
Quartz Geode
Silicon Dioxide (SiO2) in Geode form
Quartzite Pebble
Quartzite (SiO2)
Limestone
Calcite (CaCO3)
Blue Quartzite
Quartzite (specifically a variety enriched with blue-coloring minerals)
Turquoise (Dyed Howlite or Magnesite imitation)
Hydrated phosphate of copper and aluminum / CuAl6(PO4)4(OH)8·4H2O
Chert / Flint
Microcrystalline Quartz (SiO2)