Fossilized Shark Tooth (Eroded)
Carcharodon sp. or Otodus sp. fragment (likely)
Category
Browse man made material specimens identified by the Rock Identifier community.
Fossilized Shark Tooth (Eroded)
Carcharodon sp. or Otodus sp. fragment (likely)
White cabochon gemstone, likely milky chalcedony or opalite
Chalcedony: microcrystalline quartz, SiO₂; appearance may also indicate synthetic opalite glass
Paving-concrete aggregate with a rounded stone
Polymictic gravel aggregate; the central clast appears to be weathered sandstone or volcanic rock
Weathered chert or chalcedony nodule
Microcrystalline quartz (SiO₂), possibly silicified limestone or agate-like chalcedony
Beaded gemstone bracelet, likely lapis lazuli and pale quartz/agate
Lapis lazuli: lazurite-rich rock, chiefly (Na,Ca)₈(AlSiO₄)₆(S,SO)₂; pale beads are uncertain
Tumbled milky quartz
Quartz (silicon dioxide, SiO₂)
Fulgarite
Fulgurite (Lechatelierite / Vitrified Sand)
Faceted gemstone in a jewelry setting
Indeterminate from image; likely quartz, cubic zirconia, or another transparent faceted stone
Sandstone
Arenite
Engineered Quartz (Quartzite look-alike)
Silicon Dioxide (SiO2) composite
Sandstone
Sedimentary Rock (Quartz Sandstone)
Flint / Chert
Microcrystalline Quartz (SiO2)
Sandstone
Arenite (specifically sublithic or quartz arenite)
Likely iron-rich rock or weathered metallic mineral fragment
Uncertain; possibly limonite/goethite or iron-bearing slag
Red Sandstone
Quartz Arenite (iron-stained) / SiO2
Tumbled greenstone (likely serpentinite or green jasper)
Serpentinite, commonly dominated by serpentine-group minerals (Mg₃Si₂O₅(OH)₄); exact identification requires testing
Slag
Ferrous Slag (Siliceous industrial waste)
Sandstone (Pebble)
Sandstone (arenite, arkose, wacke depending on composition)
Tourmalinated quartz point
Quartz (SiO₂) with black tourmaline (schorl, NaFe²⁺₃Al₆(BO₃)₃Si₆O₁₈(OH)₄) inclusions
Dragon Vein Agate (Dyed/Treated)
Agate (SiO2)
Blue glass-like tumbled specimen
Most likely cobalt-blue slag glass or manufactured glass; not confidently identifiable as a natural mineral from the image
Chert (often called Flint)
Microcrystalline Quartz (SiO2)
Sandstone (Red/Brown Variety)
Arenite (composed primarily of SiO2 with Fe2O3 iron oxide inclusions)
Sandstone
Arenite (variable SiO2 composition)
Red glass-like crystal, likely synthetic ruby or red glass
Uncertain from image; possible corundum (ruby), Al₂O₃, or synthetic glass
Green Glass Cullet / Recycled Glass
Amorphous Silicon Dioxide (SiO2) with various metal oxides
Chert / Green Jasper
Silicon Dioxide (SiO2)
Diorite (River Pebble)
Intermediate Phaneritic Igneous Rock
Chert (Chalcedony/Agate)
Microcrystalline Quartz (SiO2)
Chert (Arrowhead Shard)
Microcrystalline silica (SiO2)
Sand Tiger Shark Tooth (Fossil)
Carcharias taurus (fossilized dentin/enameloid)
Limestone
Calcareous sedimentary rock (CaCO3)
Chert (Flint)
Chert (SiO2)
Ferrochrome Slag
Industrial Glassy Slag (Fe-Cr alloy byproduct)
Flint or chert, possibly a knapped stone tool
Microcrystalline quartz (SiO₂), commonly chalcedony with possible carbonaceous impurities
Flint (or Chert with cortex)
Silicon dioxide (SiO2)
Chert (varieties include Flint and Mudstone)
Microcrystalline Silica (SiO2)
Sandstone (Quartzose)
Arenite (primarily SiO2)
Diamond
Carbon (C)
Chert (Chocolate or Brown Flint)
Chert (SiO2)
Sandstone
Arenite (primarily SiO2)
Diamond
Carbon (C)