Amethyst
SiO2 (Silicon Dioxide 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
SiO2 (Silicon Dioxide with Iron impurities)
Bornite (Peacock Ore)
Bornite (Cu5FeS4)
Sandstone
Arenite (primarily SiO2)
Chert (Jasper influence)
Microcrystalline Quartz (SiO2)
Peacock Ore (Chalcopyrite/Bornite)
Bornite (Cu5FeS4) or iridescent treated Chalcopyrite (CuFeS2)
Milky Quartz
Quartz (SiO2)
Crazy Lace Agate
Banded Chalcedony (Microcrystalline Quartz, SiO2)
Jasper with Quartz Vein
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Chert (Iron-stained)
Silicon Dioxide (SiO2)
Sandstone (River Pebble)
Arenite (SiO2 based)
Jasper
Silicon dioxide (SiO2)
Yellow Quartz (Chalcedony or Agate)
Silicon Dioxide (SiO2)
Chert (Common Opal/Jasper variety)
Cryptocrystalline Quartz (SiO2)
Amethyst
SiO2 (Silicon Dioxide with Iron impurities)
Lapis Lazuli
Lapis Lazuli (a rock type, not a single mineral, composed primarily of lazurite, calcite, and pyrite)
Quartz (Rose or Clear variety)
Silicon Dioxide (SiO2)
Sandstone (Quartz-rich)
Sandstone (SiO2 dominated)
Quartz Geode
Silicon Dioxide (SiO2) within a secondary sedimentary structure
River Stone (likely Mudstone or Siltstone)
Lutite (Clastic sedimentary rock composed of clay and silt-sized particles)
Yellow Calcite
Calcium Carbonate (CaCO3)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Lapis Lazuli
Complex rock primarily of Lazurite ((Na,Ca)8(AlSiO4)6(SO4,S,Cl,OH)2), with Pyrite and Calcite
Bauxite
Bauxite (Al2O3·2H2O)
White Marble (Whiskey Stone)
Recrystallized Calcite / Marble (CaCO3)
Quartz (Milky Quartz)
Quartz (SiO2 - Silicon Dioxide)
Sandstone
Arenite (SiO2 based clastic rock)
Ruby (Corundum)
Aluminum Oxide (Al2O3) with Chromium traces
Quartz / Common Opal Transition
Silicon Dioxide (SiO2)
Amethyst
SiO2 (Silicon Dioxide) with Iron (Fe3+) impurities
Hand-Drawn Gengar Pokémon Card Artist Item
Lignocellulosic Fiber (Cellulose, C6H10O5) with wax-based pigment (crayon/colored pencil)
Ametrine
SiO2 (silicon dioxide)
Sandstone (with banding/weathering)
Clastic Sedimentary Rock (primarily SiO2)
Limestone
Calcite (CaCO3)
Pebble (likely Quartz or Chert)
SiO₂ (Silicon Dioxide) - referring to the likely main mineral composition, Quartz. If it's chert, the scientific name remains SiO₂ with a microcrystalline structure.
Amethyst
Silicon Dioxide (SiO2 with iron impurities)
Sandstone (with biological crust)
Arenite (SiO2 based)
Yellow Calcite
Calcium Carbonate (CaCO3)
Agate
Silicon dioxide (SiO2) - variety of chalcedony
Amethyst (Tumbled)
Silicon Dioxide with iron impurities (SiO2)
Clear Quartz
Silicon Dioxide (SiO2)
Sandstone (likely Graywacke or Arkose variant)
Clastic Sedimentary Rock (SiO2 based)
Jasper
Silicon dioxide (SiO2)