Diamond
Carbon (C)
Category
Browse antropogenic (man made) specimens identified by the Rock Identifier community.
Diamond
Carbon (C)
Chert (Chert / Flint)
Microcrystalline Quartz (SiO2)
Diamond in Kimberlite
Diamond (C in Kimberlite Matrix)
Pearl
Calcium Carbonate (mostly Aragonite), CaCO3 (with conchiolin)
Rough Diamond
Diamond (pure Carbon, C)
Diamond
Native Carbon (C)
Diamond
Carbon (C)
Sandstone
Arenite (SiO2 primarily)
Limestone
Calcium Carbonate (CaCO3)
Diamond
Diamond (Pure Carbon, C)
Coquina
Bioclastic Limestone (composed primarily of CaCO3)
Sandstone
Sedimentary Rock (Quartz arenite)
Quartzite
Quartzite (Metamorphic Quartz Sandstone)
Rough Diamond
Pure Carbon (C)
Chert (and Jasper/Chalcedony mixture)
Microcrystalline Quartz (SiO2)
Fossilized Shark Tooth (Fragment)
Elasmobranchii gen. et sp. indet. (Calcium Phosphate / Apatite fossil)
Bituminous Coal (with Anthracite or Vitrinite inclusion)
Organic-rich Sedimentary Rock (Carboniferous classification)
Rough Diamond
Diamond (pure Carbon, C)
Quartzite
Metamorphosed Quartz Sandstone
Sandstone
Sandstone (Quartz-rich Arenite / SiO2)
Limestone
Calcareous sedimentary rock (CaCO3)
Dark rounded pebble, likely basalt or slag
Probable fine-grained mafic rock; possibly basalt (plagioclase–pyroxene) or industrial iron/steel slag
Tumbled chalcedony (likely blue-gray agate)
Cryptocrystalline quartz, SiO₂; chalcedony/agate variety
Diamond (in jewelry setting)
Carbon (C)
Pearl
Aragonite (CaCO3) with Conchiolin
Pink Marble
Recrystallized Limestone (Calcium Carbonate, CaCO3)
Tree Agate
Chalcedony (SiO2)
Emerald (Rough)
Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)
Sandstone (likely Quartzose Sandstone)
Arenite
Quartzite
Silica (SiO2) quartzite
Sandstone
Arenite
Chalk
Micrite (primarily Calcium Carbonate, CaCO3)
Likely blue glass or synthetic gemstone jewelry
Uncertain; possibly synthetic spinel, cubic zirconia, or blue glass
Sandstone
Clastic Sedimentary Rock
Sandstone (with iron staining)
Quartz Arenite / Ferruginous Sandstone
Raw calcite specimen
Calcite, calcium carbonate (CaCO₃)
Chert (Flint)
Silicon Dioxide (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Polished greenstone pebble
Likely nephrite jade (tremolite–actinolite), though serpentine or greenstone is possible from appearance alone
Granite (Pegmatitic)
Phaneritic Felsic Igneous Rock
Chert (specifically White Chert or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Dumortierite in Quartz
Dumortierite (Al6O3(BO3)(SiO4)3) with Quartz (SiO2)