Pebble (likely Sandstone or Granitic Pebble)
Clastic Sediment (or specific rock type, e.g., Arenite, Granitoid Pebble)
Category
Browse organic materia (not a rock or mineral) specimens identified by the Rock Identifier community.
Pebble (likely Sandstone or Granitic Pebble)
Clastic Sediment (or specific rock type, e.g., Arenite, Granitoid Pebble)
Chert (Jasper)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified wood (Quartz/Chalcedony - SiO2)
Petoskey Stone
Hexagonaria percarinata (Fossilized Coral)
Pebble
Clast (specifically a granule or small pebble)
Banded Chert / Banded Jasper (likely a variety of Chert/Chalcedony)
Chert (microcrystalline quartz)
Chert (often called Flint)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified wood (primarily SiO2 - Silicon Dioxide/Quartz)
Chert (often called Flint or River Rock)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Black Jasper
Black Jasper (Silicate mineral - SiO2)
Amber
Succinite (fossilized resin)
Chert (often called Flint when in chalk or limestone)
Silicon Dioxide (SiO₂)
Sandstone (Weathered Cobble)
Clastic sedimentary rock (primarily SiO2)
Sandstone
Sandstone (clastic sedimentary rock)
Turquoise and Spiny Oyster (Heishi style beads)
Turquoise (CuAl6(PO4)4(OH)8·4H2O) and Spondylus (Spiny Oyster shell)
Mosasaur Tooth Fossil
Mosasaurid vertebrate fossil (Hydroxyapatite)
Petrified Wood
Silicified wood (principally SiO2)
Chert (with Limestone and Iron Oxide staining)
Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Petrified Wood
Silicified wood (primarily Quartz/Chalcedony, SiO2)
Pyrite in Limestone
Iron Sulfide (FeS2) in Calcium Carbonate (CaCO3)
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Pearl (Biogenic Mineral)
Calcium Carbonate (primarily Aragonite) with Conchiolin; CaCO3
Graphite
Graphite (Native Carbon), Formula: C
Moss Agate
Silicon Dioxide with inclusions (SiO2 + Mn/Fe oxides)
Amber
Succinite (fossilized tree resin)
Black Marble
Recrystallized Calcite (CaCO3)
Moss Agate
Silicon Dioxide (SiO2) with inclusions of Manganese or Iron oxide
Tahitian Pearl
Biogenic Calcium Carbonate (Aragonite/Calcite), CaCO3
Mother of Pearl (Nacre)
Aragonite (layered with organic polymers), CaCO3
Pearl
Organic gemstone (Calcium carbonate - CaCO3)
Purple Agate (Dyed Chalcedony)
SiO2 (Silicon Dioxide) with organic dyes
Amber
Succinite (a specific common type) or Fossilized Tree Resin (C10H16O)
Sandstone (Ferruginous)
Arenite (Siliclastic Sedimentary Rock)
Amber
Succinite (fossilized resin); C10H16O
Chert (Jasper-bearing)
Microcrystalline silica (SiO2) with iron oxide inclusions
Fossilized Shark Tooth (Basal Bone)
Otodus sp. (Mineralized Hydroxyapatite)
Amber
Succinite (organic mineraloid); Chemical formula: C10H16O
Moss Agate
Silicon Dioxide (SiO2) with inclusions
Amber
Succinite (C10H16O)
Amber
Succinite (Resinite)
Chert (Jasper variety)
Microcrystalline Quartz (SiO2)