Pyrite (Iron Pyrite)
Iron Disulfide (FeS2)
Category
Browse crystal specimens identified by the Rock Identifier community.
Pyrite (Iron Pyrite)
Iron Disulfide (FeS2)
Feldspar-rich Pegmatite
Granitic Pegmatite (principally KAlSi3O8)
Obsidian
Volcanic glass (no mineral formula due to amorphous structure, mostly SiO2)
Druzzy Quartz on Matrix
Silicon Dioxide (SiO2)
Amethyst
SiO2 (Silicon Dioxide with iron impurities)
Granite
Phaneritic Igneous Rock (composed of Quartz, Feldspar, and Mica/Amphibole)
Amethyst and Titanium Treated Druzy
Silicon Dioxide (SiO2) with trace impurities including Iron
Granite
Granite (composed primarily of Quartz SiO2, Feldspar (KAlSi3O8 – NaAlSi3O8 – CaAl2Si2O8), and Mica)
Quartz
Silicon Dioxide (SiO2)
Granite
Granite (Felsic Plutonic Rock)
Granite
Granite (composed primarily of Quartz, Feldspar, and Mica)
Granite
Phaneritic plutonic rock (mainly Quartz, Feldspar, and Mica)
Granite (weathered cobble)
Granite
Amethyst (Digital/Conceptual Representation)
Amethyst (Silicon Dioxide with iron impurities, SiO2)
Amethyst
Quartz (SiO2) with trace iron impurities
Amethyst
Quartz (Silicon Dioxide) SiO2 + Fe4
Diamond
C
Unable to Identify (Image Obscured)
Unable to identify - Image contains non-geological items
Porphyritic Rhyolite
Porphyritic Rhyolite (compositionally similar to granite)
Yellow Aventurine
Silicon Dioxide with inclusions (SiO2)
Satin Spar (Selenite)
Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O
Marble
Metamorphic rock primarily composed of Calcite (CaCO3)
Quartz Geode
Crystalline Silicon Dioxide (SiO2) in Geode form
Quartz Geode
Crystalline Silicon Dioxide (SiO2) in Geode form
Diamond
Carbon (C)
Pink Tourmaline in Quartz
Elbaite [Na(Li,Al)3Al6(BO3)3Si6O18(OH)4] in Quartz [SiO2]
Porphyritic Basalt or Andesite
Porphyritic Basalt / Andesite
Quartz Geode
Silicon Dioxide (SiO2) in a Geode body
Amethyst
SiO2 (Amethyst is a variety of Quartz)
Green Aventurine
Silicon Dioxide (Quartz with Fuchsite inclusions), SiO2
Opalite
Synthetic Opalised Glass
Clear Quartz (Tumbled)
Silicon Dioxide (SiO2)
Smoky Quartz and Citrine
Silicon Dioxide (SiO2)
Ocean Jasper
Orbicular Jasper (Silicon Dioxide with impurities, SiO2)
Citrine
Citrine (Silicon Dioxide, SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Dalmatian Jasper
Peralkaline Feldspar Rhyolite
Amethyst (Rose Quartz type)
SiO2 (Silicon Dioxide)
Milky Quartz
Silicon Dioxide (SiO2)
Aquamarine (Beryl)
Beryl (Be3Al2Si6O18 with Fe impurities)
Blue Goldstone
Synthetic Aventurescent Glass (Cobalt-doped soda-lime glass)