Chalcedony (Botryoidal/Tumbled Agate)
Silicon Dioxide (SiO2)
mineral
Category
Sedimentary (Biogenic Sediment Or Biological Remain)
Browse sedimentary (biogenic sediment or biological remain) specimens identified by the Rock Identifier community.
Sandstone (Picture Sandstone)
Arenite (primarily SiO2)
sedimentary
White Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
mineral
Collection of Minerals and Ores
Various (e.g., Uraninite (U3O8), Carbon (C), Native Gold (Au), Hematite (Fe2O3), Galena (PbS), etc.)
mineral
Amber (Cherry or Red variety)
Succinite (with various trace amounts of organic compounds)
Organic Gemstone (not a rock)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Iron Oxide cement)
sedimentary
Ammonite Fossil
Ammonoidea (Calcium carbonate - CaCO3)
sedimentary
Piddock bored rock (Boring Stone)
Ichnofossil-bearing Limestone or Mudstone (trace fossils by Pholadidae)
sedimentary
Sparkling Druzy Quartz on Matrix
Silicon Dioxide (SiO2) with iron oxide inclusions
mineral
Chert (Light Grey / Flint variant)
Cryptocrystalline Quartz (SiO2)
sedimentary
Druzy Quartz
Silicon Dioxide (SiO2)
mineral
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)
mineral
Sandstone (Ferruginous)
Arenite with Iron-oxide inclusions (SiO2 primarily)
sedimentary
Quartz (Milky/Clear variety)
Silicon Dioxide (SiO2)
mineral
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Dalmatian Stone (often misnamed Dalmatian Jasper)
Aplite (with hornblende/arfvedsonite inclusions)
igneous
Pyrite
Iron Disulfide (FeS2)
mineral
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
sedimentary
Sandstone (Quartzose Sandstone Pebble)
Arenite (primarily SiO2)
sedimentary
Anthracite Coal
Anthracite (Carbon based)
metamorphic
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Sandstone
Arenite
sedimentary
Sandstone
Clastic sedimentary rock (primarily SiO2)
sedimentary
Sandstone
Arenite (SiO2 based)
sedimentary
Sandstone
Arenite (composed primarily of SiO2)
sedimentary
Kyanite (Green and Blue varieties)
Kyanite (Al2SiO5)
mineral
Pyrite (Iron Pyrite)
Iron Disulfide (FeS2)
mineral
Sandstone (likely Greywacke or Siltstone variety)
Arenite / Siltstone (primarily SiO2)
sedimentary
Sandstone
Arenite (composed primarily of SiO2)
sedimentary
Sandstone (with Iron Staining)
Clastic Sedimentary Rock (primarily Quartz, SiO2)
sedimentary
Sandstone
Arenite (SiO2 based with quartz, feldspar, or lithic fragments)
sedimentary
Sandstone (likely Arkosic or Lithic Sandstone)
Clastic Sedimentary Rock (SiO2 with assorted minerals)
sedimentary
Sandstone
Arenite
sedimentary
River Rock (River Cobbles)
Fluvial Conglomerate Clasts (primarily composed of various minerals such as Quartz, SiO2)
sedimentary
Sandstone (Ferruginous)
Arenite with Iron Oxide cement (SiO2 + Fe2O3)
sedimentary
Gneiss
High-grade metamorphic rock (Gneiss)
metamorphic
Tiger's Eye (variations include Blue or Hawk's Eye)
Silicon Dioxide with Crocidolite inclusions (SiO2)
Metamorphic mineral
Conglomerate
Conglomerate (SiO2, Al2O3, Fe2O3, CaCo3)
sedimentary
Limonite (Iron Ore)
Goethite and related iron hydroxides (FeO(OH)·nH2O)
mineral
Lignite (Brown Coal)
Lignite (C189H155O6N3S)
sedimentary
Conglomerate
Conglomerate (clastic sedimentary rock)
sedimentary
Opal
Hydrated Amorphous Silica (SiO2·nH2O)
Mineral