Diamond
Native Carbon (C)
Category
Browse sedimentary like (industrial composite) specimens identified by the Rock Identifier community.
Diamond
Native Carbon (C)
One Pound Coin (UK)
Nickel-Brass Alloy (Cu-Zn-Ni)
Quartzite Pebble
Quartzite (primarily SiO2)
Red Garnet
Pyrope-Almandine series (Mg3Al2(SiO4)3 to Fe3Al2(SiO4)3)
Blue Sapphire (Tumbled/Polished)
Corundum (Al2O3)
Blue Sapphire
Corundum (Al2O3 - Aluminum Oxide with Iron and Titanium impurities)
Basalt
Basalt (principally composed of pyroxene and plagioclase feldspar)
Shale or Slaty Mudstone
Argillaceous sedimentary rock
Green Fluorite
Fluorite (Calcium Fluoride, CaF2)
Chert (and associated Sedimentary rocks)
Microcrystalline Silica (SiO2)
Sandstone
Arenite (composed primarily of SiO2)
Basalt
Basalt (Mafic volcanic rock)
Smoky Quartz
Silicon Dioxide (SiO2)
Anthracite Coal
Anthracite
Milky Quartz (with Iron Oxide staining)
Quartz (Silicon Dioxide - SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Yellow Quartzite (River Pebble)
Quartzite (primarily Silicon Dioxide, SiO2)
Cubic Zirconia (Simulated Diamond)
Zirconium Dioxide (ZrO2)
Milky Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Olivine (Peridot)
Magnesium Iron Silicate ((Mg, Fe)2SiO4)
Quartz Geode
Silicon Dioxide (SiO2)
Sandstone
Arenite (composed primarily of SiO2)
Fluorite (likely Fluorite on Quartz/Matrix)
Calcium Fluoride (CaF2)
Sandstone Cobble
Clastic Sedimentary (Sandstone)
Sandstone (specifically Banded Sandstone)
Clastic sedimentary rock (primarily SiO2)
Quartzite
Quartzite (primarily SiO2)
Olivine (Peridot)
Magnesium Iron Silicate (Mg, Fe)2SiO4
Anthracite Coal
Anthracite (Carbon-based metamorphic rock, 86-97% C)
Sandstone
Arenite (primarily SiO2)
Chalcedony
Chalcedony (SiO₂)
Black Tourmaline
Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)
Sandstone (Quartzite-rich)
Clastic sedimentary rock (SiO2 primary)
Limestone
Calcium Carbonate (CaCO3)
Quartz (River Pebble)
Silicon Dioxide (SiO2)
Dendritic Agate or Manganese Nodule in Chert/Limestone
Silicon Dioxide (SiO2) with Manganese Oxide (MnO2) inclusions
Sandstone
Arenite (Clastic Sedimentary Rock)
Olivine (Peridot)
Magnesium Iron Silicate (Mg,Fe)2SiO4
Sandstone
Arenite (primarily SiO2)
Chert / Flint
Chert (Microcrystalline Quartz, SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Chalcedony (Agate/Chert)
Silicon Dioxide (SiO₂)
Quartz Vein in Host Rock
Crystalline Silicon Dioxide (SiO2) in Pelitic or Shaly Matrix