Quartz (Milky/Yellowish Pebble)
Silicon Dioxide (SiO2)
Category
Browse mineral, sediment specimens identified by the Rock Identifier community.
Quartz (Milky/Yellowish Pebble)
Silicon Dioxide (SiO2)
Carved Mottled Greenish-Yellow Crystal/Glass Object
Unknown; possibly a form of quartz (chalcedony/jadeite/nephrite) or glass/resin.
Gneiss
Gneissic Metamorphic Rock (Mineral composition: Quartz, Feldspar, Amphibole/Biotite)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Quartz with Iron Staining
Silicon Dioxide (SiO2) with Limonite/Hematite inclusions
Rough Diamond
Diamond (Native Carbon, C)
Milky Quartz with Iron Inclusions
Silicon Dioxide (SiO2)
Dendritic Agate (specifically Orange/Tumbled)
Silicon Dioxide (SiO2) with Oxide Inclusions
Sandstone (Weathered Pebble)
Arenite (primarily SiO2)
Serpentine, likely a variety of Chrysoprase (green chalcedony) or a similar translucent green mineral.
Serpentine Group Minerals (e.g., Antigorite, Lizardite) or Chalcedony (SiO2) with nickel impurities for Chrysoprase green.
Hypersthene
Hypersthene (formula: (Mg,Fe)SiO3)
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Schist
Mica Schist (primarily Muscovite and Quartz)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Blue Cracked Quartz (Dyed Fire Crackle Quartz)
Silicon Dioxide (SiO2) with synthetic dye
Caribbean Calcite
Calcium Carbonate with Argonite (CaCO3)
Milk Quartz (Common White Quartz)
Quartz (Silicon Dioxide, SiO2)
Sodalite
Sodalite (Na8(Al6Si6O24)Cl2)
Garden Quartz (Lodalite)
Silicon Dioxide (SiO2) with various inclusions
Ruby
Corundum (Al2O3 with Chromium traces)
Rough Diamond
Diamond (pure Carbon, C)
Amethyst (Chevron or Banded variety)
Silicon Dioxide with Iron impurities (SiO2)
Rough Diamond
Diamond (pure carbon / C)
Quartz with Iron Staining
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Gneiss (River Cobble)
Gneiss (Foliated Metamorphic Rock)
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic volcanic rock)
Prehnite
Calcium aluminum silicate hydroxide - Ca2Al(AlSi3O10)(OH)2
Pegmatite (Granitic) with Tourmaline
Granitic Pegmatite (containing Schorl and Quartz)
Granitic Pegmatite
Pegmatite (composed primarily of Quartz, Feldspar, and Muscovite mica)
Cloudy Quartz (or Milky Quartz)
Silicon Dioxide (SiO2)
Black Obsidian
Volcanic Glass (SiO2 + impurities)
Sapphire (Corundum)
Corundum (Al2O3)
Granite
Granite (Felsic Plutonic Rock)
Schist
Lepidoblastic Mica Schist
Porphyry (likely Porphyritic Andesite or Basalt)
Porphyritic Igneous Rock
Quartz in Basalt (Xenocryst)
Silicon Dioxide (SiO2) in Mafic Igneous Volcanic Rock
Goldstone (Brown/Gold variety)
Aventurine Glass (SiO2 with Copper inclusions)
Basalt with Amygdaloidal Inclusions
Aphanitic Mafic Volcanic Rock (Basalt)
Banded Iron Formation (BIF) / Tiger Iron variety
Banded Iron Formation (predominantly Hematite, Magnetite, and Chert/Quartz - SiO2 + Fe2O3)
Red Granite
Phaneritic Felsic Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)
Red Slag Glass
Amorphous Silica (Industrial byproduct with metallic oxide dopants)