Milky Quartz
Silicon Dioxide (SiO2)
mineral
Community gallery
All rocks & minerals
Every specimen the Rock Identifier community has discovered, from desert agates to deep-sea basalts.
Anthracite Coal
Anthracite (Carbon ≥ 86%)
sedimentary
Amygdaloidal Basalt
Basalt with secondary mineral infillings (SiO2, (Ca,Na)2-3(Mg,Fe,Al)5Si8O22(OH)2)
igneous
Agate
Agate (Silicon Dioxide, SiO2)
mineral
Leopard Skin Jasper
Rhyolite (Silicon Dioxide with impurities), SiO2
igneous
Dragon Vein Agate
Chalcedony (cryptocrystalline Quartz), SiO2
mineral
Chert (Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Limonite (Gossan)
FeO(OH)·nH2O (Hydrated Iron Oxide)
mineral
Iron Slag
Anthropogenic pyrometallurgical byproduct
igneous
Scoria
Vesicular Basalt / Scoria
igneous
Conglomerate
Clastic sedimentary rock (Psephite)
sedimentary
Sandstone
Arenite
sedimentary
Pumice
Pumice (Vesicular volcanic glass)
igneous
Quartzite
Quartzite (SiO2)
metamorphic
Granite
Granite (Phaneritic Quartz-Feldspar Rock)
igneous
Vesicular Basalt
Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
igneous
Porphyritic Rhyolite
Porphyritic Rhyolite (SiO2)
igneous
Epithermal Gold Ore (in Quartz/Rhyolite matrix)
Auriferous Quartz (Au + SiO2)
mineral
Sandstone
Arenite (SiO2 dominant)
sedimentary
Chert
Microcrystalline Quartz (SiO2)
sedimentary
Basalt Pebble
Basalt
igneous
Sandstone (Greywacke)
Arenite / Lithic Wacke (SiO2 predominant)
sedimentary
River Rocks and Pebbles
Mixed Silica-rich Sediments (SiO2 based)
sedimentary
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Quartz, Sandstone, and Siltstone specimens
Silicon Dioxide (SiO2) and Clastic Sedimentary Rocks
mineral and sedimentary
Conglomerate
Conglomerate
sedimentary
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Quartz Vein in Siltstone
Siltstone with Quartz (SiO2) inclusion
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Polygenetic Conglomerate (or Breccia)
Clastic Sedimentary Rock
sedimentary
Chert (Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Flint Nodules)
Cryptocrystalline Quartz (SiO2)
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Black Tourmaline
Schorl (NaFe3Al6(BO3)3Si6O18(OH)4)
mineral
Chert (Field Stone)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Beryl (Aquamarine variety)
Beryllium Aluminum Cyclosilicate (Be3Al2Si6O18)
mineral
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Limestone (likely Tufa or Travertine)
Calcium Carbonate (CaCO3)
sedimentary
Red Jasper
Silicon Dioxide with Hematite inclusions (SiO2 + Fe2O3)
sedimentary
Chert (Chalky Flint Node)
Chert (Microcrystalline Quartz, SiO2)
sedimentary