Quartz Geode
Silicon dioxide (SiO2)
Category
Browse sedimentary or igneous (secondary formation) specimens identified by the Rock Identifier community.
Quartz Geode
Silicon dioxide (SiO2)
Banded Chert (with Quartz Vein)
Microcrystalline Silica (SiO2)
Magnetite (Iron Ore)
Magnetite (Fe3O4)
Magnetite (potentially Hematite-rich)
Magnetite (Fe3O4)
Bloodstone (Heliotrope)
Silicon Dioxide (SiO2) with inclusions of Chlorite or Actinolite
Small white quartz fragment
Quartz (silicon dioxide, SiO₂)
Chert (Jasper / Petrified Wood)
Microcrystalline Quartz (SiO2)
Quartzite with Hematite staining
Quartzite (SiO2) with iron oxide inclusions
Carnelian Agate
Chalcedony (Silicon Dioxide, SiO2)
Banded Agate (with Quartz Geode Center)
Silicon Dioxide (SiO2)
Quartz (Milky Quartz / Quartzite)
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Orange Calcite
Calcium Carbonate (CaCO3)
Magnetite / Hematite mix
Magnetite (Fe3O4) and Hematite (Fe2O3)
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Hematite
Hematite, Iron(III) oxide (Fe2O3)
Hematite Ball
Iron(III) oxide (Fe2O3)
Hematite
Iron(III) oxide (Fe2O3)
Unknown Rock Fragment
Undetermined
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
Magnetite
Fe3O4 (Iron(II,III) oxide)
Granite (weathered/river-tumbled)
Granite (Plutonic Igneous Rock)
Sulfur
Native Sulfur (S8)
Geode with Iron-Stained Quartz/Calcite
Silicon Dioxide (SiO2) or Calcium Carbonate (CaCO3) in Sedimentary Matrix
Milky Quartz
Silicon Dioxide (SiO2)
Magnetite-rich ironstone (probable magnetite ore)
Magnetite, Fe₃O₄, likely in a fine-grained ironstone matrix
Calcite
Calcium Carbonate (CaCO3)
Agate (Grey Agate Slice)
Microcrystalline Quartz (SiO2)
Vesicular basalt (possible scoria)
Basaltic volcanic rock; chiefly plagioclase, pyroxene, and iron-rich minerals, with vesicles formed by trapped gas
Gneissic Schist
Foliated Metamorphic Rock (Schist/Gneiss transition)
Milky Quartz (Vein Quartz)
Silicon Dioxide (SiO2)
Blue Lace Agate
Microcrystalline Quartz (Chalcedony), SiO2
Quartz with Iron Staining
Silicon Dioxide (SiO2) with iron oxide impurities
Unidentifiable Specimen
Undetermined
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Clear Quartz (Rock Crystal)
Quartz (Silicon Dioxide, SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Magnetite
Magnetite (Fe3O4)
Magnetite / Hematite (Iron Ore)
Magnetite (Fe3O4) or Hematite (Fe2O3)
Banded Agate
Chalcedony (Silicon Dioxide, SiO2)