Feldspar
Potassium Feldspar (KAlSi3O8)
Category
Browse minerals specimens identified by the Rock Identifier community.
Feldspar
Potassium Feldspar (KAlSi3O8)
Milky quartz
Quartz, silicon dioxide (SiO₂)
Milky quartz (iron-stained quartz)
Quartz, silicon dioxide (SiO₂)
Milky quartz (quartz fragment)
Quartz, silicon dioxide (SiO₂)
Orange Calcite
Calcite (CaCO3)
Quartz
Silicon Dioxide (SiO2)
Quartz pebble
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Feldspar (Plagioclase / Potassium Feldspar)
Feldspar Group (KAlSi3O8 - NaAlSi3O8 - CaAl2Si2O8)
Milky quartz (rough quartz fragment)
Quartz, silicon dioxide (SiO₂)
Milky quartz fragment
Quartz (silicon dioxide, SiO₂)
Rounded quartz-rich pebble
Likely microcrystalline quartz (SiO₂), possibly milky quartz or a pale quartzite fragment
Clear quartz (likely quartz crystal fragment)
Quartz, silicon dioxide (SiO₂)
Milky quartz fragments
Quartz (silicon dioxide, SiO₂)
Milky quartz (likely quartz vein fragment)
Quartz, silicon dioxide (SiO₂)
Milky quartz (rough quartz crystal)
Quartz, silicon dioxide (SiO₂)
Pink Feldspar
Potassium Feldspar (KAlSi3O8)
Granite Pebble
Granite
Septarian (Dragon Stone)
Septarian Nodule (Aragonite, Calcite, Limestone)
Granite Pebble
Granite (Felsic intrusive igneous rock)
Magnetite / Hematite rich ore
Magnetite (Fe3O4) or Hematite (Fe2O3)
Basalt with Olivine (Peridot)
Basalt containing (Mg,Fe)2SiO4
Magnetite (Lodestone)
Iron(II,III) oxide (Fe3O4)
Polished multicolored mineral pebble, possibly ruby-in-zoisite
Ruby-bearing zoisite (zoisite: Ca₂Al₃(SiO₄)₃(OH); ruby: corundum, Al₂O₃)
Chrysocolla-bearing copper mineral specimen (probable turquoise/chrysocolla mix)
Chrysocolla, Cu₂H₂Si₂O₅(OH)₄·nH₂O, with possible turquoise CuAl₆(PO₄)₄(OH)₈·4H₂O and copper oxides
Schist
Mica Schist
Serpentinite
Serpentinite, dominated by serpentine-group minerals (lizardite, chrysotile, antigorite)
Tumbled quartz (likely rose or milky quartz)
Quartz, silicon dioxide (SiO₂)
Lapis Lazuli
(Na,Ca)8(AlSiO4)6(S,SO4,Cl)1-2 (Complex silicate rock)
Limonite / Ironstone Nodule
Hydrated Iron Oxide (FeO(OH)·nH2O)
Quartz with Actinolite or Tourmaline inclusions
Silicon Dioxide (SiO2) with Ca2(Mg,Fe)5Si8O22(OH)2 or Tourmaline group inclusions
Green Aventurine
Silicon dioxide with Fuscite inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)
Galena in Quartz Matrix
Lead Sulfide (PbS) in Silicon Dioxide (SiO2)
Quartz Mineral
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Quartz with Mineral Inclusions
Silicon Dioxide (SiO2) with accessory minerals
Fossil Shark Tooth
Otodus sp. or Carcharocles sp. (likely fossilized Chondrichthyes)
Green Schist
Greenschist (Chlorite Schist)
Milky quartz (raw quartz crystal)
Quartz, silicon dioxide (SiO₂)
Foliated metamorphic rock, likely gneiss or mica schist
Quartz–feldspar–mica metamorphic rock; exact identification is uncertain from the photograph
Limonite (Iron Ore / Ochre)
Hydrated iron(III) oxide-hydroxide (FeO(OH)·nH2O)
Orthoclase Feldspar
Orthoclase (KAlSi3O8)