Weathered sandstone fragment
Sandstone, chiefly quartz (SiO₂) with feldspar and iron-oxide cement
sedimentary
Category
Organic (Non Geological)
Browse organic (non geological) specimens identified by the Rock Identifier community.
Slag (Industrial Byproduct)
Ferrous/Non-ferrous Silicate
igneous (artificial/anthropogenic)
Quartzite
Metamorphic Quartzite (SiO2)
metamorphic
Obsidian
Volcanic Glass (Amorphous Silica)
igneous
Obsidian
Obsidian (Volcanic Glass, primarily SiO2)
igneous
Quartzite
Quartzite (primarily SiO2)
metamorphic
Laterite
Laterite (Iron and Aluminum-rich residual soil/rock)
sedimentary
Weathered limestone with possible fossil or calcite coating
Limestone; primarily calcium carbonate (CaCO₃), chiefly calcite
sedimentary
Amber
Succinite (formula varies, primarily C10H16O)
Mineraloid (Organic)
Petrified Wood
Silicified wood (SiO2)
fossil
Libyan Desert Glass
Libyan Desert Glass (SiO2 with trace elements)
mineral (impactite)
Blue Goldstone
Aventurine Glass
Man-made mineral simulant (Glass)
Fossiliferous Kalkstein (Marl/Sandstone)
Fossiliferous calcarenite/siltstone
sedimentary
Quartzite
Quartzite (SiO2)
metamorphic
Quartzite Pebble
Quartzite (primarily SiO2)
metamorphic
Siderite Concretion in Shale
Iron carbonate (FeCO3) in Mudstone/Shale matrix
sedimentary
Pearl necklace with small blue-green gemstone accents
Pearls: nacre, chiefly aragonite (CaCO₃) and conchiolin; accents appear to be turquoise or similar opaque blue-green stone
gemstone
Metal Chain (Likely Steel or a Steel Alloy)
Steel (primarily iron and carbon); specific alloy unknown
Man-made Object (Metal/Alloy)
Quartzite
Quartzite (SiO2)
metamorphic
Quartzite
Metamorphic Quartzite (SiO2)
metamorphic
Moss Agate
Silicon Dioxide with inclusions (SiO2 + Fe/Mn/Mg)
mineral
Petrified Wood (Agatized/Silicified Wood)
Silicified Paleoxylon (primarily SiO2)
sedimentary
Tektite (Indochinite)
Tektite (High-silica impact glass)
igneous
Chert (Jasper variety)
Silicon dioxide (SiO2)
sedimentary
Fossilized Horn Coral
Order Rugosa (Rugose Coral)
sedimentary
Green aventurine (likely)
Quartzite dominated by quartz (SiO₂), colored green by fuchsite mica or chlorite
mineral
Black Obsidian
Volcanic Glass (Amorphous Silicon Dioxide)
igneous
Green cabochon gemstone, likely nephrite jade
Nephrite jade—interlocking amphibole fibers, chiefly tremolite-actinolite, Ca₂(Mg,Fe)₅Si₈O₂₂(OH)₂
gemstone
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
mineral
Chert / Jasper
Cryptocrystalline Silica (SiO2)
sedimentary
Chert (Flint)
Microcrystalline Quartz or Cryptocrystalline Silica (SiO2)
sedimentary
Chert (Flint)
Microcrystalline Silicon Dioxide (SiO2)
sedimentary
Pyrite
Iron Sulfide (FeS2)
mineral
Chert (Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Quartzite
Quartzite (SiO2)
metamorphic
Glass / Silicon Dioxide (Man-made)
SiO2 (Amorphous Silicon Dioxide)
Amorphous Solid
Blue Slag Glass
Amorphous Silica (Industrial byproduct)
Antropogenic (Man-made glass byproduct)
Obsidian
Obsidian (volcanic glass)
igneous
Concretion
Septarian Concretion (Fragmentary)
sedimentary
Cullet Glass (Slag)
Amorphous Silicon Dioxide (Man-made)
Mineraloid
Chert (Flint variety)
Silicon Dioxide (SiO2)
sedimentary
Pyrite
Iron Sulfide (FeS2)
mineral