Fossilized Solitary Rugose Coral
Order Rugosa (commonly Horn Coral)
Category
Browse organic mineraloid specimens identified by the Rock Identifier community.
Fossilized Solitary Rugose Coral
Order Rugosa (commonly Horn Coral)
Chert (containing a small fossil)
Microcrystalline Quartz (SiO2)
Banded Gneiss
Gneiss (pronounced 'nice')
Pearl
Calcium Carbonate (Aragonite) - CaCO3
Brain Coral Fossil
Family Mussidae or Merulinidae (Order Scleractinia)
Pearl
Calcium Carbonate (primarily Aragonite and Calcite), CaCO3
Gastropod Steinkern (Internal Mold Fossil)
Gastropoda (Class); Internal mold or 'Steinkern' composed of Calcium Carbonate (CaCO3) or Sedimentary matrix
Pearl
Aragonite (CaCO3) with Conchiolin
Horn Coral Fossil
Rugosa (Order Rugosa)
Fossiliferous Limestone
Fossiliferous Calclutite / Bio-calcarenite (CaCO3)
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Yellow Calcite
Calcium Carbonate (CaCO3)
Coprolite
Coprolite
Fossilized Coral (Petoskey Stone / Favosites)
Favosites (extinct genus of tabulate coral)
Sandstone (with potential trace fossils)
Clastic sedimentary rock (primarily SiO2)
Limestone Pebble
Sedimentary Calcium Carbonate (CaCO3)
Banded Iron Formation (BIF)
Banded Iron Formation containing Hematite (Fe2O3) and Magnetite (Fe3O4)
Chert (Common Opal/Agate inclusion)
Microcrystalline Quartz (SiO2)
Travertine (Tufa)
Chemical Sedimentary Limestone (CaCO3)
Limestone (Flagstone)
Fossiliferous Limestone (CaCO3)
Fossiliferous Limestone (with Coralline Inclusions)
Calcium Carbonate (CaCO3)
Greenstone (Epidote/Chlorite-rich Metabasalt)
Greenschist / Epidosite (Ca2(Al,Fe)3(SiO4)3(OH))
Coral Fossil (Favosites)
Favosites (Extinct genus of tabulate corals)
Fossiliferous Limestone
Biogenic Calcium Carbonate (CaCO3)
Bryozoan Fossil
Phylum Bryozoa (commonly known as 'moss animals')
Limestone
Calcium Carbonate (CaCO3)
Chalk
CaCO3 (primarily Calcium Carbonate), biogenic sedimentary rock
Fossiliferous Limestone (Crinoidal)
Bioclastic Limestone (predominantly CaCO3)
Fossilized Coral (Petoskey-like or Favosites)
Anthozoa (Fossilized Coral)
Aragonite
Aragonite (Carbonate mineral), CaCO3
Chert Nodule
Microcrystalline Quartz (SiO2)
Piddock bored rock (Boring Stone)
Ichnofossil-bearing Limestone or Mudstone (trace fossils by Pholadidae)
Sandstone with Liesegang Rings
Arenite with secondary Iron oxide (Limonite/Goethite) precipitation
Chert
Siliceous sedimentary rock (predominantly microcrystalline quartz, SiO2)
Sandstone (with Lichen)
Arenite (primarily SiO2)
Pearl (as a biogenic mineral/gemstone)
Calcium Carbonate (mostly Aragonite), CaCO3
Fossiliferous Limestone
Calcium Carbonate (CaCO3) with Bioclastic Inclusions
Shale
Fissile Mudrock (Clay-rich Sedimentary Rock)
Shale
Fissile Mudstone (primarily composed of phyllosilicate minerals like kaolinite, montmorillonite, and illite)
Pumice
Pumice (Vesicular Rhyolite/Andesite)
Shale with Siltstone layering
Sedimentary Clastic Rock (Mudstone/Shale)
Fossilized Favosites (Honeycomb Coral)
Favosites (Genus), Phylum Cnidaria, Class Anthozoa