Amethyst
Silicon Dioxide (SiO2) with Iron impurities
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.
Amethyst
Silicon Dioxide (SiO2) with Iron impurities
Limestone (specifically a Crushed Aggregate fragment)
Calcium Carbonate (CaCO3)
Sandstone (Quartzite-rich)
Clastic sedimentary rock (SiO2 primary)
Banded Chert or Agate
Silicon Dioxide (SiO2)
Amethyst
Silicon dioxide (SiO2)
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily SiO2 with Fe2O3 oxides)
Calcite
Calcium Carbonate (CaCO3)
Calcite
Calcite (CaCO 3)
Chert (Jasper variety)
Cryptocrystalline Quartz (SiO2)
Unable to identify - Image contains non-geological items
Orange Calcite
Calcite (Calcium Carbonate, CaCO3)
Quartz (White/Milky with Iron Staining)
Silicon Dioxide (SiO2)
Amethyst
SiO2 (Silicon Dioxide with iron impurities and irradiation)
Quartz (Milky/Vein Quartz)
Silicon Dioxide (SiO2)
White Precious Opal
Hydrated Silica (SiO2·nH2O)
Chert (Yellow Jasper/Flint)
Microcrystalline Quartz (SiO2)
Fluorite (often called Rainbow Fluorite or Purple-Green Fluorite)
Calcium Fluoride (CaF2)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Gneiss
Gneiss (High-grade metamorphic rock)
Orange Calcite (Dogtooth/Cluster)
Calcium Carbonate (CaCO3)
Amethyst Sage Agate
Silicon Dioxide (SiO2) with trace minerals (Manganese/Iron oxides)
Quartz / Citrine Quartz
Silicon Dioxide (SiO2)
Pyrite in Matrix (Quartz/Schist)
Iron Sulfide (FeS2)
Unidentifiable Specimen
Undetermined
Jasper with Quartz Veining
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Chert (Jasper/Flint variant)
Silicon Dioxide (SiO2)
Amethyst Quartz (Amethyst Geode)
Silicon Dioxide (SiO2) with iron impurities
Quartz Geode
Silicon Dioxide (SiO2)
Banded Calcite (often sold as Mexican Onyx or Aragonite)
Calcite/Aragonite (Calcium Carbonate, CaCO3)
Optical Calcite (Iceland Spar)
Calcite (Calcium Carbonate, CaCO3)
Dendritic Jasper
Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions
Quartz
Quartz (SiO₂)
Fossiliferous Limestone
Calcite (CaCO3) Rich Bio-sedimentary Rock
Chert (and Jasper blend)
Chert (Microcrystalline Quartz, SiO2)
Mookaite Jasper
Silicified Radiolarite (SiO2)
Lapis Lazuli
Na6Ca2(Al6Si6O24)(S,SO4,Cl)1-2 (primarily containing Lazurite with inclusions of Calcite and Pyrite)
Sandstone
Arenite (primarily SiO2)
Banded Sandstone (Quartzite-rich)
Clastic Sedimentary Rock (SiO2 with Iron Oxide impurities)
Chert (Nodule)
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Ferruginous Chert
Microcrystalline Quartz (SiO2) with Iron Oxides