Gneiss
Gneiss (High-grade metamorphic rock)
Category
Browse sedimentary rock (metamorphosed) specimens identified by the Rock Identifier community.
Gneiss
Gneiss (High-grade metamorphic rock)
Greenschist
Greenschist facies rock
Fossiliferous Limestone
Limestone (composed primarily of calcite with included fossils CaCO3)
Dolomite or Limestone (Carbonate Rock)
CaMg(CO3)2 (Dolomite) or CaCO3 (Limestone / Calcite)
Gneiss
Gneiss (High-grade Metamorphic Rock)
Dyed Agate (Tumbled)
Silicon Dioxide (SiO2) - stained microcrystalline quartz
Gneiss
Gneiss (High-grade regional metamorphic rock)
Clear Quartz Crystal
Quartz (Silicon Dioxide, SiO2)
Fossil Shell Fragment (possibly Brachiopod or Bivalve)
Calcium Carbonate (CaCO3) - Phylum Brachiopoda or Mollusca
Banded Chert (River Cobble)
Microcrystalline Quartz (SiO2)
Quartz-veined Siltstone
Siltstone with Quartz (SiO2) veins
Green Jasper
Silicon Dioxide (SiO2) with iron silicate inclusions
Green Jasper
Silicon Dioxide (SiO2) with impurities
Chert Pebble with Quartz Veining
Microcrystalline Quartz (SiO2)
Sandstone
Arenite (primarily SiO2)
Chert (and Limestone) River Cobble
Microcrystalline Quartz (SiO2) within Calcium Carbonate (CaCO3)
Ferruginous Sandstone
Arenite with Hematite/Limonite cement
River Jasper (Chert/Chalcedony mix)
Silicon Dioxide (SiO2) with iron oxide and chlorite inclusions
Jasper (Iron-stained Chert)
Silicon Dioxide (SiO2)
Red Jasper
Jasper (Silicon Dioxide based crypto-crystalline Quartz with Iron inclusions)
Chert (Jasper/River Pebble)
Silicon Dioxide (SiO2)
Red Chert (Jasper)
Chert / Microcrystalline Quartz (SiO2)
Clear Quartz
Silicon Dioxide (SiO2)
Ferruginous Breccia
Breccia with Iron-rich (Hematite/Goethite) Matrix
Yellow Jasper
Silicon Dioxide with iron inclusions (SiO2)
Sandstone
Arenite (SiO2 principal)
Pink Botswana Agate
Silicon Dioxide (SiO₂), a cryptocrystalline variety of Quartz and Chalcedony
Sandstone (likely Quartzose Sandstone)
Arenite
Chert with Quartz Veining
Silicon Dioxide (SiO2)
Sandstone with Manganese Dendrites/Oxide coatings
Arenite with Pyrolusite and Romanechite (MnO2)
Ferruginous Sandstone
Sandstone (arenite) with Limonite/Goethite cement
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
Chert (Jasper type)
Microcrystalline Quartz (SiO2)
Chert (Yellow/Tan)
Microcrystalline Quartz (SiO2)
Bauxite (Pisolitic Bauxite)
Bauxite (mixture of Hydrous Aluminum Oxides)
Oolite (Ooids)
Oolitic Limestone (Principal mineral: Calcite, CaCO3)
Chert (Jasper/Mudstone)
Silicon Dioxide (SiO2)
Chert (Nodular Chert)
Silicon Dioxide (SiO2)
Chert (variations include Flint or Jasper)
Silicon Dioxide (SiO2)
Coquina
Bioclastic Limestone (Calcium Carbonate, CaCO3)
Limestone
Calcium Carbonate (CaCO3)
Coquina
Bioclastic Limestone (composed primarily of CaCO3)