Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Category
Browse mineral precipitate (anthropogenic context) specimens identified by the Rock Identifier community.
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Rhodonite in Quartz Matrix
Rhodonite (Manganese Silicate - (Mn,Fe,Mg,Ca)SiO3)
Ferruginous Quartz
Silicon Dioxide with Hematite/Limonite impurities (SiO2 + Fe2O3)
Yellow Quartz (Citrine Quartz or Yellow Jasper)
Silicon Dioxide (SiO2) with iron impurities
Botryoidal Chalcedony
Silicon Dioxide (SiO2)
Septarian Nodule
Septarian Concretion
Azurite-Malachite (often called Azerite Malachite or Azurmalachite)
Azurite (Cu3(CO3)2(OH)2) and Malachite (Cu2CO3(OH)2)
Orange Calcite
Calcite (CaCO3)
Red Jasper
Red Jasper (variety of Chalcedony, SiO₂)
Yellow Jasper
Cryptocrystalline Quartz (SiO2)
Sandstone (Pebble)
Arenite / Clastic Sedimentary Rock
Amazonite (likely mixed with other feldspars/minerals)
Amazonite is a variety of Microcline, which is a tectosilicate mineral, formula KAISi3O8. The mixed beads could include other feldspars or quartz.
Chakra Stone Tower (Composite Multi-Mineral)
Crystalline Silicon Dioxide composite (SiO2) with various inclusions
Sandstone (likely Quartzose)
Sandstone (Principally SiO2)
Gneiss
Gneiss
Sandstone
Arenite (primarily SiO2)
Grey River Stone (Quartz-rich Quartzite/Siltstone)
Quartzite / Meta-siltstone (primarily SiO2)
Vesicular Basalt (Amygdaloidal)
Amygdaloidal Basalt
Fluorite (Purple variety)
Calcium Fluoride (CaF2)
Shale or Siltstone
Sedimentary Clastic Rock (Variable mineral composition including quartz and clay minerals)
Red Jasper
Silicon Dioxide (SiO2) with Hematite inclusions
Amazonite
Potassium aluminum silicate (KAlSi3O8)
Tanzanite (Rough)
Blue Zoisite (Ca2Al3(SiO4)3(OH))
Malachite and Azurite on Matrix
Cu2CO3(OH)2 (Malachite) / Cu3(CO3)2(OH)2 (Azurite)
Rutilated Quartz
Silicon Dioxide (SiO2) with Titanium Dioxide (TiO2) inclusions
Amethyst
Amethyst (Silicon Dioxide with iron impurities), SiO2
Amethyst
Amethyst (SiO2 with Iron impurities)
Rough Citrine Quartz
Silicon Dioxide (SiO2) with iron impurities
Moldavite
Tektite (Impact Glass), ~80% SiO2 + Al2O3
Stichtite in Serpentine (Atlantasite)
Mg6Cr2CO3(OH)16·4H2O in Mg3Si2O5(OH)4
Citrine (likely Heat-Treated Amethyst)
Silicon Dioxide (SiO2)
Vanadinite on Matrix
Vanadinite (Pb5(VO4)3Cl)
Chalcedony (Yellow Agate)
Cryptocrystalline Quartz (SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Emerald (Faceted Gemstone)
Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)
Gold Nugget
Native Gold (Au)
Desert Rose
Gypsum (variety Selenite) or Barite, CaSO4·2H2O
Opal
Hydrated Amorphous Silica (SiO2·nH2O)
Amethyst
Crystalline Quartz (SiO2) with iron impurities
Herkimer Diamond (Quartz)
Silicon Dioxide (SiO2)
Fire Opal (in matrix)
Hydrated Silica (SiO2·nH2O)
Opal
Hydrated silica (SiO2·nH2O)