Goethite pseudomorph after Pyrite
Goethite (FeO(OH)) pseudomorph after Pyrite (FeS2)
Category
Browse mineral (man made composite) specimens identified by the Rock Identifier community.
Goethite pseudomorph after Pyrite
Goethite (FeO(OH)) pseudomorph after Pyrite (FeS2)
Amethyst
Silicon dioxide (SiO2) with iron impurities
Sunstone
Oligoclase (Plagioclase Feldspar), (Na,Ca)(Si,Al)4O8
Fire Opal in Host Rock
Amorphous Hydrous Silica (SiO2·nH2O)
Desert Rose (Gypsum/Baryte)
Hydrated Calcium Sulfate (CaSO4·2H2O)
Quartz Geode with Goethite/Hematite
Silicon Dioxide (SiO2) with Iron Oxides
Malachite with Chrysocolla
Copper carbonate hydroxide (Cu2CO3(OH)2) and Hydrated copper silicate (Cu,Al)2H2Si2O5(OH)4·nH2O
Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
Biotite Mica
Biotite (K(Mg,Fe)3AlSi3O10(OH,F)2)
Smoky Quartz (Herkimer-style)
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
Larimar
Pectolite (a blue variety of Pectolite)
Quartz Geode
Crystalline Silicon Dioxide (SiO2) within a nodule
Sandstone
Arenite
Sandstone with Iron Oxide Staining
Arenite with Limonite/Hematite alteration
Ironstone Concretion
Siderite or Hematite Concretion
Desert Rose (Sand Barite/Gypsum Rose)
Barium Sulfate (BaSO4) or Hydrated Calcium Sulfate (CaSO4·2H2O)
Red Sandstone
Arenite (primarily SiO2 with Fe2O3)
Turquoise
Hydrated phosphate of copper and aluminum, CuAl6(PO4)4(OH)8·4H2O
Dendritic Agate
Silicon Dioxide (SiO2) with inclusions of manganese or iron oxides
Turquoise
CuAl6(PO4)4(OH)8·4H2O (Hydrous phosphate of copper and aluminium)
Ironstone (with Limonite/Goethite)
Ferruginous Sedimentary Rock (contains Limonite FeO(OH)·nH2O and Hematite Fe2O3)
Azurite and Malachite on Matrix
Azurite: Cu3(CO3)2(OH)2; Malachite: Cu2CO3(OH)2
Brown Sandstone
Arenite (primarily Quartz and Feldspar, with Iron Oxide cement)
Turquoise
CuAl6(PO4)4(OH)8·4H2O
Potassium Feldspar and Quartz
KAlSi3O8 (Potassium Feldspar) and SiO2 (Quartz)
Geode (Unopened)
Crystalline Quartz or Chalcedony filled Geode (SiO2)
Granite and Igneous Mix
Phaneritic Felsic to Mafic Intrusive Rocks
Blue Apatite
Apatite-(CaF), Ca5(PO4)3F
Iron-stained Quartz (Gossan/Limonite-coated Quartz)
Silicon Dioxide (SiO2) with Hydrated Iron Oxides (FeO(OH)·nH2O)
Chakra Tumbled Stone Set
Various (including Amethyst [SiO2], Sodalite [Na8(Al6Si6O24)Cl2], Green Aventurine [SiO2], Red Jasper [SiO2], etc.)
Green Fluorite
Calcium Fluoride (CaF2)
Quartz (Citrine or Iron-Stained)
Silicon Dioxide (SiO2)
Green Fluorite
Fluorite (Calcium Fluoride) - CaF2
Fluorite
Calcium Fluoride (CaF2)
Obsidian
Volcanic glass (SiO2 - Silicon Dioxide with impurities)
Micaceous Rock (likely Muscovite Schist/Gneiss or a Muscovite-rich Specimen)
Predominantly Muscovite (KAl2(AlSi3O10)(F,OH)2), often found in rocks like Muscovite Schist or Muscovite Gneiss.
Mica Schist
Mica Schist (predominantly Muscovite or Biotite sheet silicates)
Quartz (Druzy) in host rock
SiO₂ (Silicon Dioxide) as Quartz, with unspecified host rock components (likely silicates and iron oxides)
Tiger's Eye
Tiger's eye (Pseudomorph of Quartz after Crocidolite), SiO2
Sandstone (likely River-tumbled Picture Sandstone)
Arenite (predominantly SiO2 with iron oxide impurities)