Quartz
Quartz (Silicon Dioxide, SiO2)
Category
Browse the purple specimen is a mineral (amethyst); the white specimen is a sedimentary rock (limestone or marble). specimens identified by the Rock Identifier community.
Quartz
Quartz (Silicon Dioxide, SiO2)
Quartz Geode with Goethite/Hematite
Silicon Dioxide (SiO2) with Iron Oxides
Sandstone (Painted)
Arenite (primarily SiO2)
Common Opal in Host Rock
Hydrated Silica (SiO2·nH2O)
White Quartz Pebble
Silicon Dioxide (SiO2)
Fossiliferous Limestone (with Crinoids/Coral)
Fossiliferous Limestone (CaCO3)
Plume Agate
Silicon Dioxide (SiO2)
Agate Geode
Silicon Dioxide (SiO2) - variety Chalcedony/Quartz
Chert (variations include Flint or Jasper)
Silicon Dioxide (SiO2)
Sandstone
Arenite (primarily SiO2)
Quartz Geode
Silicon Dioxide (SiO2)
Rainbow Fluorite
Fluorite (Calcium Fluoride, CaF2)
Quartzite
Quartzite (primarily SiO2)
Quartz (likely macrocrystalline variety)
Quartz (SiO₂)
Crushed Limestone
Calcium Carbonate (CaCO3)
Barite
Barium Sulfate (BaSO4)
Yellow Chert
Sedimentary cryptocrystalline quartz (SiO2)
Calligraphy Stone
Mariam Jasper (Fossiliferous Limestone with Hematite and Iron)
Aquamarine with Ruby Accent
Beryllium Aluminum Silicate (Be3Al2Si6O18) with Aluminum Oxide (Al2O3)
Quartz
Quartz (SiO2 - Silicon Dioxide)
Amethyst (Chevron or Banded)
Silicon Dioxide (SiO2) with iron impurities
Coquina / Fossiliferous Limestone
Bioclastic Limestone (CaCO3)
Sandstone Concretion with Quartz Center
Sedimentary Clastic Rock (SiO2 matrix with Quartz core)
Sandstone (Quartzose)
Arenite (primarily SiO2)
Chert
Silicon dioxide (SiO2)
Green Jasper
Silicon Dioxide (SiO2) with impurities
Lapis Lazuli
Na8[Al6Si6O24]n(S,Cl,SO4,OH)2
Amethyst
Amethyst (SiO2 - Silicon Dioxide with iron impurities)
Clear Quartz Cluster
Silicon Dioxide (SiO2)
Jasper (Chert)
Silicon Dioxide (SiO2)
Chert (specifically Jasper/Carnelian variety)
Microcrystalline quartz (SiO2)
Quartz
Silicon Dioxide (SiO2)
Quartz (Druzy)
Silicon Dioxide (SiO2)
Chert (or Flint)
Chert (Sedimentary Cryptocrystalline Sio2)
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
Amethyst (Tumbled)
Amethyst (Silicon Dioxide, SiO2 + Fe4+)
Lapis Lazuli
Lapis Lazuli (A complex rock primarily composed of Lazurite: (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)
Amethyst Geode Cathedral
Amethyst (Silicon Dioxide - SiO2 with Iron impurities)
Quartz (Milky or Druzy Quartz)
Silicon Dioxide (SiO2)
Sandstone with Liesegang Rings
Arenite with Iron Oxide Concretions
Quartz (in matrix)
Quartz (SiO₂)
Banded Calcite (Mexican Onyx)
Calcium Carbonate (CaCO3)