Lapis Lazuli
Lapis Lazuli (a rock, not a single mineral; primary mineral is Lazurite (Na,Ca)8(AlSiO4)6(S,SO4,Cl)1-2
Metamorphic rock
Category
Not A Natural Rock (Man Made Composite)
Browse not a natural rock (man made composite) specimens identified by the Rock Identifier community.
Granite (Dioritic variant)
Phaneritic Felsic Igneous Rock (primarily Quartz, Feldspar, and Mica)
igneous
Sandstone
Arenite (SiO2 based)
sedimentary
Basalt
Basalt (Mafic volcanic rock)
igneous
Sandstone (Pebble)
Arenite (composed primarily of SiO2)
sedimentary
Chert (often called Flint)
Chert (Microcrystalline or cryptocrystalline Silica, SiO2)
sedimentary
Limestone (specifically Travertine or Tufa)
Calcium Carbonate (CaCO3)
sedimentary
Herkimer Diamond
Quartz (Silicon Dioxide) - SiO2
mineral
Granite
Phaneritic Igneous Rock (composed primarily of Quartz, Alkali Feldspar, and Plagioclase)
igneous
Bauxite
Bauxite (Al(OH)3, γ-AlO(OH), and α-AlO(OH))
sedimentary
Sandstone (likely Arkosic)
Clastic Sedimentary Rock (primarily SiO2 with Feldspar)
sedimentary
Belemnoit (Fossil)
Belemnoidea (Order), Rostrum / Guard
sedimentary
Sandstone (Ferruginous)
Arenite (Fe2O3 stained)
sedimentary
Shale
Clastic sedimentary rock (primarily clay and silt minerals)
sedimentary
Bituminous Coal (with Anthracite or Vitrinite inclusion)
Organic-rich Sedimentary Rock (Carboniferous classification)
sedimentary
Sandstone (with Iron Staining)
Clastic sedimentary rock (SiO2 with Fe2O3 oxides)
sedimentary
Shale
Argillaceous Rock
sedimentary
Smoky Quartz and Chalcedony Geode Fragment
Silicon Dioxide (SiO2)
mineral
Sandstone (Calcareous Sandstone)
Calcareous Sandstone (primarily SiO2 with CaCO3 cement)
sedimentary
Sandstone
Clastic Sedimentary Rock (primarily Quartz, SiO2)
sedimentary
Painted River Pebble (likely Basalt or Greywacke)
Aphanitic Lithic Clast with Anthropogenic Pigment coating
Sedimentary or Igneous
Banded Chert (River Stone)
Silicon Dioxide (SiO2)
sedimentary
Sandstone (Ferruginous)
Arenite with Iron-Oxide Cement
sedimentary
Sandstone
Clastic sedimentary rock (primarily SiO2)
sedimentary
Granite
Phaneritic Plutonic Felsic Rock
igneous
Herkimer Diamond (Quartz Crystal)
Silicon Dioxide (SiO2)
mineral
Granodiorite
Granodiorite (Quartz + Plagioclase + Alkali Feldspar + Biotite/Hornblende)
igneous
Sandstone (Quartz-rich)
Arenite (primarily SiO2)
sedimentary
Granite
Granite (Phaneritic Quartz-Feldspar intrusive rock)
Igneous
Desert Rose (also known as Sand Rose)
Gypsum (CaSO4·2H2O) or Barite (BaSO4) with sand inclusions
mineral
Crinoid Fossil Stem Segment
Class Crinoidea (Echinodermata)
sedimentary
Sandstone
Clastic sedimentary rock (primarily SiO2)
sedimentary
Smoky Quartz
Silicon Dioxide (SiO2)
mineral
Granite
Phaneritic Felsic Intrusive Igneous Rock
igneous
River Cobble (Quartzite)
Meta-orthoquartzite
metamorphic
Sandstone (Quartzose)
Sandstone (clastic sedimentary rock, primarily SiO2)
sedimentary
Ferruginous Sandstone (Ironstone)
Clastic Sedimentary Rock (composed of SiO2 with Fe2O3/FeO(OH) cement)
sedimentary
Sandstone (likely Arkosic)
Arenite (SiO2 with KAlSi3O8)
sedimentary
Malaysian 50 Sen Coin
Coinage (specific alloy unknown without metallurgical analysis, but typically brass or bronze for this denomination and era)
Man-made object (coin)
Sandstone (lithic/greywacke variant)
Clastic sedimentary rock (primarily SiO2 with rock fragments)
sedimentary
Dyed Agate (Tumbled)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
mineral
Cullet Glass (Industrial Slag Glass)
Amorphous Silica (SiO2) with metallic oxide impurities
Man-made byproduct (often mistaken for Obsidian or Emerald)