Sodalite
Sodalite (Na8(Al6Si6O24)Cl2)
Category
Browse organic (often found by beachcombers) specimens identified by the Rock Identifier community.
Sodalite
Sodalite (Na8(Al6Si6O24)Cl2)
Milky Quartz
Silicon Dioxide (SiO2)
Orange Calcite
Calcium Carbonate (CaCO3)
Chert (Gravel)
Chert (Cryptocrystalline silicon dioxide, SiO2)
Lapis Lazuli
Lazurite-rich metamorphic rock (approx. (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)
Banded Calcite or Travertine
Calcium Carbonate (CaCO3)
Quartzite
Quartzite (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Granite Pebble
Felsic intrusive igneous rock (composition: Quartz, Feldspar, Mica)
Obsidian
Volcanic glass (SiO2-rich)
Quartzite
Quartzite
Quartz (White/Milky Quartz)
Silicon Dioxide (SiO2)
Gravel Pebble (Likely Quartzite or Basalt)
Quartzite (or Macrocrystalline Quartz)
Banded Gneiss
Gneiss (complex metamorphic silicate rock)
Quartzite (River Stone)
Quartzite (SiO2)
Zebra Jasper
Silicon Dioxide (SiO2) with impurities
Chalcedony (Agate)
Chalcedony (Cryptocrystalline Quartz, SiO2)
Mica (Lepidolite or Muscovite)
Phyllosilicate mineral (KAl2(AlSi3O10)(OH)2 for Muscovite)
Chrysocolla in Matrix
Chrysocolla (Cu,Al)2H2Si2O5(OH)4·nH2O
Banded Chert (Agate/Jasper blend)
Microcrystalline Quartz (SiO2)
Mahogany Obsidian
Volcanic Glass (predominantly SiO2 with inclusions of Hematite or Magnetite)
Agate
SiO2
Quartzite River Rock
Quartzite (SiO2)
Sandstone (likely Arkosic)
Clastic Sedimentary Rock (primarily SiO2 with Feldspar)
Fossiliferous Limestone (Chert/Clay mixed)
Calcium Carbonate (CaCO3) / Silicon Dioxide (SiO2)
Agate
Cryptocrystalline quartz (SiO2)
Picture Jasper
Impure variety of silica (SiO2)
Quartzite
Quartzite (SiO2)
Dyed Agate Slice
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Cullet Glass (Man-made Glass Slag)
Amorphous Silica (SiO2) with chemical additives
Chert (Flint)
Silicon Dioxide (SiO2)
Chert Geode or Nodule
Microcrystalline Quartz (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with Ferric Iron inclusions
Lavender Quartz (appearing as beads) and Druzy Quartz
Silicon Dioxide (SiO2)
Granite Pebble
Intrusive Felsic Igneous Rock (Granite)
Moqui Marble
Hematite Concretion (Iron Oxide Concretion)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Orange Quartz
Crystalline Silicon Dioxide (SiO2) with iron oxide inclusions
Fuchsite
Chromium-rich Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2)
Chrysocolla
Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2O)
Quartzite
Metamorphic rock predominantly composed of Quartz (SiO2)
Chert
Microcrystalline Quartz (SiO2)