Moss Agate
Silicon Dioxide with inclusions (SiO2 + Mn/Fe oxides)
Category
Browse organic (anthropogenic) specimens identified by the Rock Identifier community.
Moss Agate
Silicon Dioxide with inclusions (SiO2 + Mn/Fe oxides)
Amber
Succinite (fossilized tree resin)
Pyrite in Shale
Iron Sulfide (FeS2) in Argillaceous Shale
Amber
Succinite
Shale (with minor calcite veining)
Clastic sedimentary rock (primarily clay minerals and quartz)
Moss Agate
Silicon Dioxide (SiO2) with mineral inclusions of hornblende or chlorite
Amber
Succinite (specifically for Baltic amber); Fossilized Tree Resin (C10H16O)
Liesegang Ring Siltstone
Siltstone with iron oxide Liesegang bands
Amber
Succinite (C10H16O)
Limestone
Calcium Carbonate (CaCO3)
Fossil Shell (Bivalve)
Class Bivalvia (Likely a member of the Ostreidae or Gryphaeidae family), CaCO3
Coral Fossil (Scleractinia)
Scleractinia (Order), primarily CaCO3 (Aragonite or Calcite)
Amber
Amber (C10H16O)
Fossiliferous Limestone
Limestone (CaCO3 - Calcium Carbonate)
Dendritic Agate (Tree Agate)
Chalcedony (Silicon Dioxide, SiO2) with Manganese or Iron Oxide inclusions
Basaltic Tuff / Volcanic Breccia
Pyroclastic Breccia / Lithic Tuff
Pyrite in Shale
Iron Disulfide (FeS2) in Argillaceous Shale
Shale (or Mudstone)
Siltstone/Argillite (composed mainly of clay and silt-sized particles)
Green Moss Agate
Agate (Silicon Dioxide - SiO2) with inclusions of hornblende or chlorite
Pink Opal
Amorphous Hydrous Silica (SiO2·nH2O)
Amber
Succinicum (Succinite); C10H16O
Ferruginous Sandstone (Ironstone)
Sedimentary rock with Limonite/Goethite cement
Tree Agate (or Moss Agate)
Dendritic Agate (Silicon Dioxide - SiO2)
Pink Opal
Hydrated Silica (SiO2·nH2O)
Pink Opal
Hydrated Amorphous Silica (SiO2·nH2O)
Amber
Succinite (specifically for Baltic amber; fossilized tree resin)
Moss Agate and Hematite
Silica (SiO2) with fibrous inclusions of Manganese or Iron; Hematite (Fe2O3)
Shale or Slaty Mudstone
Argillaceous sedimentary rock
Shale
Fissile Clay-dominant Mudrock (SiO2, Al2O3, K2O, Na2O, CaO, MgO)
Fossiliferous Limestone
CaCO3 (principally Calcite or Aragonite)
Chert (Beach Pebble)
Silicon Dioxide (SiO2)
Chert (specifically Red Chert/Jasper variety)
Silicon Dioxide (SiO2)
Chert (Iron-stained)
Chert (Microcrystalline and Cryptocrystalline Quartz, SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (Yellow Jasper variant)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert (specifically a weathered Chert nodule or fragment)
Chert; Microcrystalline or Cryptocrystalline Quartz (SiO2)
River Stone (Chert/Siltstone)
Cryptocrystalline Quartz (SiO2) with trace impurities
Fossil Shark Tooth
Carcharodon or Carcharias fossil (Vertebrate Fossil)
Chert (with Quartz Veining)
Microcrystalline silicon dioxide (SiO2)
Chert (often referred to as Flint)
Chert (Microcrystalline Quartz, SiO2)
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Chert (often called Flint or Jasper)
Cryptocrystalline quartz (SiO2)