Sandstone (Weathered Pebble)
Arenite (primarily SiO2)
Category
Browse mineral (tectosilicate) specimens identified by the Rock Identifier community.
Sandstone (Weathered Pebble)
Arenite (primarily SiO2)
Hypersthene
Hypersthene (formula: (Mg,Fe)SiO3)
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Gneiss (River Cobble)
Gneiss (Foliated Metamorphic Rock)
Caribbean Calcite
Calcium Carbonate with Argonite (CaCO3)
Blue Cracked Quartz (Dyed Fire Crackle Quartz)
Silicon Dioxide (SiO2) with synthetic dye
Milk Quartz (Common White Quartz)
Quartz (Silicon Dioxide, SiO2)
Sodalite
Sodalite (Na8(Al6Si6O24)Cl2)
Amethyst (Chevron or Banded variety)
Silicon Dioxide with Iron impurities (SiO2)
Garden Quartz (Lodalite)
Silicon Dioxide (SiO2) with various inclusions
Ruby
Corundum (Al2O3 with Chromium traces)
Rough Diamond
Diamond (pure Carbon, C)
Quartz with Iron Staining
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Rough Diamond
Diamond (pure carbon / C)
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)
Granite
Phaneritic Intrusive Igneous Rock (composed of Quartz, Feldspar, and Mica)
Septarian Nodule (Septarian Dragon Stone)
Septarian concretion (composition: Calcite CaCO3, Aragonite CaCO3, and Limestone/Clay)
Basalt with Amygdaloidal Inclusions
Aphanitic Mafic Volcanic Rock (Basalt)
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)
Banded Iron Formation (BIF) / Tiger Iron variety
Banded Iron Formation (predominantly Hematite, Magnetite, and Chert/Quartz - SiO2 + Fe2O3)
Red Slag Glass
Amorphous Silica (Industrial byproduct with metallic oxide dopants)
Granite
Phaneritic Plutonic Felsic Rock (KAlSi3O8 - SiO2 - NaAlSi3O8)
Red Granite
Phaneritic Felsic Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)
Giallo Ornamental Granite
Phaneritic Igneous Rock (composed of Quartz, Feldspar, and Mica)
Granite (Alkali-feldspar rich)
Phaneritic Felsic Igneous Rock (Major components: KAlSi3O8, SiO2)
Biotite Gneiss
Gneiss (complex mixture including Biotite K(Mg,Fe)3AlSi3O10(F,OH)2 and Quartz/Feldspar)
Sandstone
Arenite (primarily SiO2)
Blue Aventurine
Quartzite with Dumortierite inclusions (SiO2)
Amygdaloidal Basalt
Amygdaloidal Basalt
Green Aventurine
Quartzite (variety Aventurine) with Fuchsite inclusions (K(Al,Cr)2(AlSi3O10)(OH)2)
Granite
Granite (Felsic Plutonic Rock)
Chert / Flint
Cryptocrystalline quartz (SiO2)
Greenschist
Chlorite schist
Black Obsidian
Volcanic Glass (SiO2 + impurities)