Milky Quartz
Silicon Dioxide (SiO2)
Category
Browse mineral description (anthropogenic material) specimens identified by the Rock Identifier community.
Milky Quartz
Silicon Dioxide (SiO2)
Sandstone
Quartz arenite / Lithic sandstone
Ironstone concretion
Siderite or Limonite concretion (FeCO3 or FeO(OH)·nH2O)
Sandstone
Arenite (SiO2 primarily)
Sandstone (Red Sandstone)
Arenite (predominantly SiO2 with Fe2O3 cement)
Sandstone (Quartzose)
Arenite (primarily SiO2)
Sandstone
Arenite
Sandstone
Clastic Sedimentary Rock (primarily SiO2)
Jasper
Silicon dioxide (SiO2) with impurities
Blue-green chrysocolla rough specimen
Chrysocolla, hydrated copper aluminosilicate; commonly associated with malachite, quartz, and limonite
Greenschist
Greenschist (Chlorite-actinolite schist)
Travertine (Tufa)
Chemical Limestone (CaCO3)
Sandstone (with Laminations)
Clastic sedimentary rock (primarily Quartz-based)
Red Sandstone
Arenite (high iron oxide content)
Sandstone (Red Sandstone)
Arenite (SiO2 based with Fe2O3 staining)
Green Spot Jasper (Kiwi Jasper / Sesame Jasper)
Partially altered granitic rock rich in quartz, microcline feldspar, and tourmaline or amphibole inclusions
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified wood (principally SiO2)
Shale
Clastic Sedimentary Rock
Shale
Shale (Lutite)
Sandstone
Sandstone (composed predominantly of Quartz, SiO2, with Feldspar and Clay minerals)
Quartz-rich metamorphic rock (likely mica schist or gneiss)
Quartz–feldspar–mica assemblage; probable biotite schist/gneiss
Black Obsidian cabochon
Volcanic Glass (SiO2 + impurities)
Chert (Jasper variety)
Chert (SiO2)
Synthetic Marbled Aggregate (Footwear Component)
Ethylene-vinyl acetate (Croslite™)
Vesicular Basalt (Amygdaloidal)
Vesicular Basalt (Fe-Mg rich extrusive volcanic rock)
Grey Jasper (Tumbled Quartz variant)
Jasper (Silicon Dioxide, SiO2)
Bauxite
Aluminum ore (mixture of gibbsite Al(OH)3, boehmite γ-AlO(OH), and diaspore α-AlO(OH))
Quartz (Grain)
Silicon Dioxide (SiO2)
Sandstone (Ferruginous)
Arenite (composed primarily of SiO2 with Fe2O3 staining)
Sandstone
Arenite (primarily SiO2)
Mica Schist
Mica Schist (primarily Muscovite or Biotite sheet silicates)
Blue-dyed magnesite beads (often sold as “turquoise howlite”)
Magnesite, MgCO₃; commonly dyed blue and possibly marketed as dyed howlite, Ca₂B₅SiO₉(OH)₅
Sandstone
Sandstone (SiO2 dominated)
Sandstone (Quartzose Sandstone)
Arenite (primarily SiO2)
Sandstone
Arenite (primarily SiO2)
Granite Water-Worn Pebble
Intermediate to Felsic Phaneritic Igneous Rock
Tiger Shark Fossil Tooth
Galeocerdo cuvier (fossilized)
Tumbled quartz pebble
Quartz (silicon dioxide, SiO₂)
Likely tumbled quartz/chalcedony
Quartz (SiO₂), possibly milky quartz or pale chalcedony
Tumbled jasper (likely brecciated or orbicular jasper)
Microcrystalline quartz (chalcedony), SiO₂, with iron-oxide and other mineral inclusions
Snakeskin Agate
Agate (Cryptocrystalline Quartz, SiO2)