Amethyst
SiO2 (Silicon Dioxide with Iron impurities)
Category
Browse mineral (pseudomorph) specimens identified by the Rock Identifier community.
Amethyst
SiO2 (Silicon Dioxide with Iron impurities)
Milky Quartz
Silicon Dioxide (SiO2)
Amethyst
Silicon dioxide with iron impurities (SiO2)
Celestine (or Celestite)
Strontium sulfate (SrSO4)
Tree Agate
Silicon Dioxide (SiO2) with Dendritic Inclusions
Amethyst (Faceted)
Silicon Dioxide with Iron impurities (SiO2)
Rhodonite
Rhodonite (Manganese silicate, (Mn,Fe,Mg,Ca)SiO3)
Smoky Quartz
Quartz (Silicon Dioxide) - SiO2
Larimar
Blue Pectolite (NaCa2Si3O8(OH))
Citrine
Silicon Dioxide (SiO2) with iron impurities
Rose Quartz
SiO2 (Silicon Dioxide with trace amounts of titanium, iron, or manganese)
Raw Emerald
Beryl (Be3Al2(SiO3)6) with Cr/V impurities
Milky Quartz with Iron Staining
Silicon Dioxide (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Amazonite
Microcline (KAlSi3O8)
Amethyst
Silicon Dioxide with Iron impurities (SiO2)
Labradorite
(Ca, Na)(Al, Si)4O8 (Plagioclase Feldspar)
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
Chalcedony (Quartz Var.)
Silicon Dioxide (SiO2)
Amethyst
Silicon Dioxide with Iron impurities (SiO2)
Herkimer Diamond
Quartz (Silicon Dioxide, SiO2)
Optical Calcite (Iceland Spar)
Calcite (Calcium Carbonate, CaCO3)
Herkimer Diamond
Quartz (Silicon Dioxide, SiO2)
Quartz Geode in Sedimentary Matrix
Silicon Dioxide (SiO2) within a limestone/dolostone host
Hematite
Hematite (Fe2O3)
Rutilated Quartz
SiO2 with TiO2 inclusions
Yellow Quartz (Citrine or Iron-stained Quartz)
Silicon Dioxide (SiO2)
Pyrite
Iron Sulfide (FeS2)
Fossiliferous Rock (likely Dinosaur Fossil in Matrix)
Permineralized Vertebrate Fossil (Calcium Carbonate/Silica replaced bone material)
Ammonite Fossil
Ammonoidea (Calcium carbonate or Pyrite replaced)
Shale
Lutaceous Sedimentary Rock
Garnet (likely Almandine or Pyrope)
Garnet Group (e.g., Almandine: Fe3Al2(SiO4)3; Pyrope: Mg3Al2(SiO4)3)
Leopard Skin Jasper
Chalcedony (cryptocrystalline quartz) with inclusions
Muscovite Mica
Muscovite (KAl2(AlSi3O10)(OH)2)
Garnet (Almandine/Pyrope variety)
Silicate mineral group; typically Fe3Al2(SiO4)3 (Almandine) or Mg3Al2(SiO4)3 (Pyrope)
Peridot (likely, based on color and appearance)
Olivine group mineral, specifically (Mg,Fe)2SiO4 (Forsterite-Fayalite solid solution series)
Garnet (Almandine)
Almandine Garnet (Fe3Al2(SiO4)3)
Sugilite
Sugilite (KNa2(Fe,Mn,Al)2Li3Si12O30)
Geode (unopened)
Chert / Chalcedony Geode (SiO2)
Pink Granite
Phaneritic intrusive igneous rock (Felsic)
Coarse-grained Quartz with Feldspar inclusions
Crystalline Quartz (SiO2) with Orthoclase/Plagioclase Feldspar inclusions
Foliated Gneiss (River-Worn Pebble)
Gneiss (High-grade Regional Metamorphic Rock)