Agate
Silicon Dioxide (SiO2)
Category
Browse mineral like byproduct (technogenic) specimens identified by the Rock Identifier community.
Agate
Silicon Dioxide (SiO2)
Iron-stained Quartz
Silicon Dioxide with Hematite/Limonite impurities (SiO2 + Fe2O3)
Banded Agate / Chalcedony
Silicon Dioxide (SiO2) with trace impurities
Quartz Pebble
Silicon Dioxide (SiO2)
Chromium (Chrome)
Chromium (Cr)
Banded Agate (often called Brown Agate or Chalcedony)
Silicon Dioxide (SiO2)
Banded Agate
Chalcedony (Silicon Dioxide, SiO2)
Grey Agate (Tumbled)
Silicon Dioxide (SiO2)
Quartz (Smoky/Milky variant)
Silicon Dioxide (SiO2)
Sandstone
Arenite (SiO2 based)
Chert (vuggy variety)
Microcrystalline silica (SiO2)
Garnet
Almandine (Fe3Al2(SiO4)3)
Agate
Silicon dioxide (SiO2) - variety of chalcedony
Tumbled Carnelian and Quartz Mix
Silicon Dioxide (SiO2) with iron oxide impurities
Chert (Flint) with Glauconite
Microcrystalline Quartz (SiO2)
Quartz (Riverstone / Cobble)
Silicon Dioxide (SiO2)
Quartz Geode
Silicon Dioxide (SiO2)
Smoky Quartz
Quartz (Silicon Dioxide) - SiO2
Amber
Succinite
Agate (specifically Chalcedony nodule)
Silicon Dioxide (SiO2)
Mahogany Obsidian
Obsidian (volcanic glass with hematite/magnetite inclusions)
Sandstone (with Iron Staining)
Clastic Sedimentary Rock (primarily SiO2)
Barite Rose on Marcasite
Barium Sulfate (BaSO4) on Iron Sulfide (FeS2)
Granite Pebble
Felsic Intrusive Igneous Rock (composed of Quartz, Feldspar, and Mica)
Black Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
River Cobble (Gneiss/Migmatite)
Gneissic Metamorphic Rock (composed mainly of Quartz, Feldspar, and Biotite)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Specular Hematite
Hematite (Fe2O3)
Sandstone
Clastic sedimentary rock (primarily SiO2)
River Quartz Pitting/Cobble
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Ferruginous Sandstone
Arenite with Iron-Oxide cement (Fe2O3 · nH2O)
Chalcedony (Botryoidal Agate)
Silicon Dioxide (SiO2)
White Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Carnelian (Orange Agate/Chalcedony)
Silicon Dioxide (SiO2) - variety of Chalcedony
Synthetic Sapphire and Ion-X Glass
Single-crystal Alumina (Al2O3) and Ion-strengthened Aluminosilicate Glass
Botryoidal Quartz / Calcite Geode crust
Silicon Dioxide (SiO2) or Calcium Carbonate (CaCO3)
Ferruginous Sandstone
Ferruginous Clastic Sedimentary Rock
Quartz
Silicon Dioxide (SiO2)
Green Aventurine
Silicon Dioxide (Quartz) with inclusions of Fuchsite (K(Al,Cr)2(AlSi3O10)(OH)2)
Banded Agate
Cryptocrystalline Quartz (SiO2)