Shale (or Mudstone)
Siltstone/Argillite (composed mainly of clay and silt-sized particles)
sedimentary
Category
Organic (Biological Organism)
Browse organic (biological organism) specimens identified by the Rock Identifier community.
Green Moss Agate
Agate (Silicon Dioxide - SiO2) with inclusions of hornblende or chlorite
mineral
Pink Opal
Amorphous Hydrous Silica (SiO2·nH2O)
mineral
Fossilized Coral (Petoskey-like or Favosites)
Anthozoa (Fossilized Coral)
sedimentary
Ferruginous Sandstone (Ironstone)
Sedimentary rock with Limonite/Goethite cement
sedimentary
Tree Agate (or Moss Agate)
Dendritic Agate (Silicon Dioxide - SiO2)
mineral
Pink Opal
Hydrated Silica (SiO2·nH2O)
mineral
Pink Opal
Hydrated Amorphous Silica (SiO2·nH2O)
mineraloid
Amber
Succinite (specifically for Baltic amber; fossilized tree resin)
Organic (Sedimentary-associated)
Moss Agate and Hematite
Silica (SiO2) with fibrous inclusions of Manganese or Iron; Hematite (Fe2O3)
mineral
Chert
Siliceous sedimentary rock (predominantly microcrystalline quartz, SiO2)
Sedimentary
Amber
Succinite (fossilized resin)
mineraloid
River Pebble (Siltstone/Mudstone)
Clastic sedimentary rock
sedimentary
Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with inclusions of Chlorite, Manganese, or Iron
mineral
Jasper with Agate and Quartz Inclusions
Silicon Dioxide (SiO2) - Chalcedony / Quartz aggregate
sedimentary
Amber
Succinite (fossilized resin); C10H16O
mineraloid
Fossiliferous Limestone
Calcium Carbonate (CaCO3) with Bioclastic Inclusions
sedimentary
Amber
Succinite (C10H16O)
mineraloid
Shale
Fissile Mudrock (Clay-rich Sedimentary Rock)
sedimentary
Moss Agate
Silicon Dioxide with inclusions (SiO2)
mineral
Sandstone Pebble
Arenite (primarily SiO2)
sedimentary
Moss Agate
Silicon Dioxide (SiO2) with inclusions of manganese or iron oxide
mineral
Moss Agate
Silicon Dioxide with inclusions (SiO2 + Fe/Mn/Mg)
mineral
Amber
Succinate (Fossilized Tree Resin)
mineraloid
Moss Agate
Cryptocrystalline Quartz (SiO2 with Manganese or Iron Oxide inclusions)
mineral
Amber with Inclusion
Succiniferous fossil resin (C10H16O)
mineraloid
Chert (specifically Blue Chert or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Sandstone (with Lichen)
Arenite (primarily SiO2)
sedimentary
Pink Opal (Common Opal)
Amorphous Hydrated Silica (SiO2·nH2O)
mineral
Pearl (as a biogenic mineral/gemstone)
Calcium Carbonate (mostly Aragonite), CaCO3
mineral
Amber
(C10H16O)n – an amorphous organic substance, primarily composed of polymerized isoprenoids.
Mineral
Petrified Wood
Silicified Wood (primarily SiO2)
sedimentary
Chert (Black Chert/Flint)
Silicon Dioxide (SiO2)
sedimentary
Moss Agate
Silicon Dioxide with inclusions (SiO2 + Mn/Fe oxides)
mineral
Amber
Succinite (fossilized tree resin)
mineral
Pyrite in Shale
Iron Sulfide (FeS2) in Argillaceous Shale
sedimentary
Shale (with minor calcite veining)
Clastic sedimentary rock (primarily clay minerals and quartz)
sedimentary
Moss Agate
Silicon Dioxide (SiO2) with mineral inclusions of hornblende or chlorite
Mineral (variety of Chalcedony)
Amber
Succinite (specifically for Baltic amber); Fossilized Tree Resin (C10H16O)
Organic Mineraloid
Amber
Succinite (fossilized resin); C10H16O
mineraloid
Liesegang Ring Siltstone
Siltstone with iron oxide Liesegang bands
sedimentary
Amber
Succinite (C10H16O)
mineraloid