Amethyst
SiO2 (Silicon Dioxide with Iron impurities)
Category
Browse mineral specimen specimens identified by the Rock Identifier community.
Amethyst
SiO2 (Silicon Dioxide with Iron impurities)
Green Opal
Opal (Hydrated silica, SiO2·nH2O)
Unidentified dark pebble
Undetermined; possibly polished basalt, chert, or iron-rich stone
Chrysocolla
Hydrated copper phyllosilicate, (Cu,Al)2H2Si2O5(OH)4·nH2O
Quartz Pebble
Silicon Dioxide (SiO2)
Bull Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Chrysocolla
Hydrated copper phyllosilicate, (Cu,Al)2H2Si2O5(OH)4·nH2O
Sandstone (with Limonite staining)
Arenite (primarily SiO2 with FeO(OH)·nH2O)
Quartz with Iron Staining and Chlorite Inclusions
Silicon Dioxide (SiO2)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Chalcedony (Botryoidal/Chalcedony Rose)
Silicon Dioxide (SiO2)
Black Onyx and Mother of Pearl
Cryptocrystalline Quartz (SiO2) and Nacre (Calcium Carbonate)
River Pebble (Gneiss or Granite)
Metamorphic Rock (likely Gneiss or Granitic composition)
Banded Sandstone (Water-worn Pebble)
Arenite with mineral banding
White Quartz Pebble
Silicon Dioxide (SiO2)
Quartz (Chatoyant or Milky variety)
Silicon Dioxide (SiO2)
Ferruginous Quartz (River Pebble)
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Satin Spar (often marketed as Selenite)
Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O
Quartz
Silicon Dioxide (SiO2)
Citrine Geode Fragment
Silicon Dioxide (SiO2) with iron impurities
Amethyst (Raw Quartz)
Silicon Dioxide (SiO2) with iron impurities
Amethyst (Scepter/Double Terminated Point)
Silicon Dioxide (SiO2)
Quartz-Veined Gneiss or Metamorphic Rock with Quartz Veins
Quartz-veined metamorphic rock (Silicate mineral assemblage)
Quartz-veined Sandstone Pebble
Quartzite-veined Arenite
Diamond (in a metal ring setting)
Diamond (Pure Carbon, C)
Pyrite
Iron Sulfide (FeS2)
Quartz
Silicon Dioxide (SiO2)
Sandstone with Dendritic Inclusions
Quartzose Sandstone
Garden Quartz (Lodalite)
Silicon Dioxide (SiO2) with mineral inclusions
Green Calcite or Prasiolite (Green Quartz)
Calcium carbonate (CaCO3) or Silicon dioxide (SiO2)
Tumbled Agate
Silicon Dioxide (SiO2)
Tumbled Peach Quartz
Silicon Dioxide (SiO2)
Tumbled Rose Quartz
Silicon Dioxide (SiO2)
Tumbled Amethyst
Silicon Dioxide (SiO2)
Tumbled Agate
Silicon Dioxide (Chalcedony variety), SiO2
Amethyst Geode
Silicon Dioxide (SiO2) with iron impurities
Milky Quartz
Silicon Dioxide (SiO2)
Agate (Carnelian / Chalcedony)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Milky Quartz
Silicon Dioxide (SiO2)
Chalcedony (Carnelian)
Silicon Dioxide (SiO2)
Quartz pebble with host matrix
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)