Chert (Flint nodule)
Chert (SiO2)
Category
Browse sedimentary (synthetic) specimens identified by the Rock Identifier community.
Chert (Flint nodule)
Chert (SiO2)
Jasper
Silicon dioxide (SiO2) with impurities
Limonite / Ironstone
Limonite (Hydrated Iron Oxide) - FeO(OH)·nH2O
Chalcedony (Common Opal or Agate)
Silicon Dioxide (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Yellow Calcite
Calcium Carbonate (CaCO3)
Quartz Geode
Silicon Dioxide (SiO2) within a geode
Jasper
Silicon Dioxide (SiO2)
Kyanite
Kyanite (Al2SiO5)
Quartz Geode
Silicon Dioxide (SiO2)
Pyrite
Iron Sulfide (FeS2)
Limonite
Limonite (Hydrous iron oxides, predominantly Goethite FeO(OH)·nH2O)
Pyrite and Sunstone
Iron Sulfide (FeS2) and Plagioclase Feldspar ((Ca,Na)Al(Al,Si)Si2O8)
Carnelian
Carnelian (SiO2)
Chalcedony (Agate/Carnelian type)
Silicon Dioxide (SiO2)
Satin Spar (Selenite)
Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O
Pebble or Cobble (likely composed of sandstone or conglomerate)
Clastic Sedimentary Rock (specific name like sandstone, conglomerate, or breccia would require microscopic analysis of clast size and angularity)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Sandstone (Quartz Sandstone)
Clastic sedimentary rock (primarily SiO2)
Limestone
Calcite-rich Sedimentary Rock (CaCO3)
Quartz
Silicon Dioxide (SiO2)
Pyrite
Iron Pyrite (FeS₂)
Chert
Channery Chert (Microcrystalline Quartz)
Quartz Geode
Crystalline Silicon Dioxide (SiO2) in Geode
Assorted Tumbled Gemstones
Mixed oxides and silicates (including Quartz, Chalcedony, and Feldspar variants)
Gneiss
Gneiss (High-grade metamorphic rock)
Greenish Metamorphic Rock (likely containing epidote or chlorite)
Metamorphic rock, possibly epidosite or greenstone
Chalcedony
Silicon Dioxide (SiO2)
Botryoidal Quartz
Silicon Dioxide (SiO2)
Quartz (Milky or Yellow variety)
Silicon Dioxide (SiO2)
Chert (Flint)
Chert (SiO2)
Galena
Lead(II) sulfide (PbS)
Quartz Geode (Cracked)
Silicon Dioxide (SiO2)
Dyed Howlite (Dyed Red)
Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)
Quartz Geode (with Calcite influence)
Silicon Dioxide (SiO2) with possible Calcium Carbonate (CaCO3)
Yellow Calcite
Calcium Carbonate (CaCO3)
Chert (Jasper variety)
Microcrystalline Quartz (SiO2)
Optical Calcite (Iceland Spar)
Calcite (CaCO3)
Garnet (Almandine)
Almandine, Fe3Al2Si3O12
Limonite/Goethite (Iron Ore)
Hydrous ferric oxides (FeO(OH)·nH2O)
Specular Hematite with Quartz and Limonite
Hematite (Fe2O3) with Quartz (SiO2) and Limonite (FeO(OH)·nH2O)
Quartz (Milky/Common)
Silicon Dioxide (SiO2)