Pegmatite with muscovite mica
Granitic pegmatite; quartz (SiO₂), feldspar, and muscovite (KAl₂(AlSi₃O₁₀)(OH)₂), locally biotite/tourmaline
igneous
Category
Mineral (Native Element Alloy)
Browse mineral (native element alloy) specimens identified by the Rock Identifier community.
Learn about Mineral (Native Element Alloy) in the encyclopedia
View all →
Pegmatite with Black Tourmaline
Granitic Pegmatite with Schorl (NaFe2+3Al6(Si6O18)(BO3)3(OH)3OH)
igneous
Green Aventurine
Aventurine Quartz (SiO2 with Fuchsite inclusions)
mineral
Quartz Geode
Silicon Dioxide (SiO2) within a geode
mineral
Pegmatite (with Quartz and Feldspar)
Granitic Pegmatite
igneous
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Chert (often called Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
sedimentary
Schist
Mica Schist
metamorphic
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (variations include Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chert / Chalcedony
Microcrystalline Quartz (SiO2)
sedimentary
Chert (specifically Jasper or Flint variant)
Cryptocrystalline Quartz (SiO2)
sedimentary
Limestone with Quartz or Calcite Veining
Calcium Carbonate (CaCO3) matrix with SiO2 or CaCO3 inclusions
sedimentary
Schist
Mica Schist
metamorphic
Note: Item is not a geological specimen
n/a
none
Limonite (Iron Ore)
Hydrated iron(III) oxide-hydroxide (FeO(OH)·nH2O)
mineral
Lepidolite
K(Li,Al)3(Si,Al)4O10(F,OH)2
mineral
Desert Rose
Gypsum (variety Selenite) or Barite: CaSO4 · 2H2O
mineral
Turquoise in Matrix
CuAl6(PO4)4(OH)8·4H2O (Hydrous phosphate of copper and aluminium)
mineral
Green Aventurine
Silicon Dioxide (SiO2) with Fuchsite inclusions
metamorphic
Eudialyte
Eudialyte (Na4(Ca,Ce)2(Fe2+,Mn,Y)ZrSi8O22(OH,Cl)2)
mineral
Limonite / Goethite (Ironstone)
Hydrated Iron(III) Oxide-Hydroxide FeO(OH)wnH2O
sedimentary
Schist with Biotite and Quartz
Biotite-Quartz Schist (Fe,Mg,Al silicate mix)
metamorphic
Quartz pebble
SiO2
mineral
Quartz Cobble (River Pebble)
Quartz (Silicon Dioxide - SiO2)
mineral
Quartz Geode
SiO2 (Silicon Dioxide)
sedimentary
Red Sandstone (Iron-rich)
Ferruginous Sandstone (SiO2 with Iron Oxides)
sedimentary
Quartz-veined Sedimentary Rock
Hydrothermally veined Clastic Sedimentary Rock (SiO2 veins in Matrix)
sedimentary
Sandstone (likely with Quartz Veining)
Arenite (primarily SiO2)
sedimentary
Sandstone
Arenite (lithic or quartz sandstone)
sedimentary
Fossilized Bone Fragment
Permineralized Vertebrate Bone (Hydrox yapatite replaced by Silica or Calcite)
sedimentary
Cubic Zirconia (CZ) Jewelry
Zirconium dioxide (ZrO2)
mineral (synthetic)
White Sapphire
Corundum (Al2O3)
mineral
Granite Pebble (River Rock)
Granite (composed primarily of Quartz, Feldspar, and Mica)
igneous
Amazonite
Microcline Feldspar (KAlSi3O8)
mineral
Howlite
Howlite (Ca2B5SiO9(OH)5)
mineral
Amethyst (with Pyrite and other minerals)
Silicon Dioxide (SiO2)
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Calcite
Calcite (CaCO3)
Mineral
Coquina / Shelly Sandstone
Calcareous Sandstone / Coquina
sedimentary
Amethyst
Quartz (Silicon Dioxide with Iron impurities), SiO2
mineral
Orthoclase Feldspar
KAlSi3O8 (Potassium Aluminum Silicate)
mineral