Basalt (Greenstone)
Amygdaloidal Basalt / Chloritized Basalt
Category
Browse mineral like byproduct (technogenic) specimens identified by the Rock Identifier community.
Basalt (Greenstone)
Amygdaloidal Basalt / Chloritized Basalt
Dendritic Opal
Hydrated Silica with Manganese inclusions (SiO2·nH2O)
Gneiss
Gneiss
Snowflake Obsidian
Hydrated Volcanic Glass (primarily SiO2) with Cristobalite inclusions
Fluorite
Fluorite (Calcium Fluoride, CaF2)
Potassium Feldspar
Orthoclase (KAlSi3O8)
Granite
Granite (Felsic Plutonic Rock)
Obsidian (Gold Sheen)
Obsidian (SiO2 + impurities)
Serpentinite
Serpentinite (composed primarily of serpentine minerals like antigorite, chrysotile, and lizardite)
Quartz Vein in Sedimentary Rock
Silicon Dioxide (SiO2) with host Chert or Limestone
Jasper (Green Jasper/Chert)
Silicon Dioxide (SiO2)
Sandstone
Arenite (primarily SiO2)
Petrified Wood
Silicified Wood (SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Yellow Calcite
Calcium Carbonate (CaCO3)
Quartz (specifically Clear Quartz or Rock Crystal)
Silicon Dioxide (SiO2)
Chalcedony (Common Opal variant)
Silicon dioxide (SiO2) with varying levels of hydration
Basalt
Basalt (Mafic Extrusive Igneous Rock)
Basalt (Vesicular)
Vesicular Basalt
Petrified Wood
Silicified wood (Quartz, SiO2)
Howlite
Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Lepidolite
K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2 (Lithium-bearing Phyllosilicate)
Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic Volcanic Rock)
Sandstone
Arenite
Marble
Recrystallized Calcite (CaCO3) or Dolomite (CaMg(CO3)2)
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Limonite
Hydrous Iron Oxide (often Goethite FeO(OH), Lepidocrocite γ-FeO(OH), and other amorphous iron oxyhydroxides)
Blue Sapphire
Corundum (Al2O3) with iron and titanium impurities
Almandine Garnet
Iron aluminum silicate (Fe3Al2(SiO4)3)
Almandine Garnet
Almandine (Fe3Al2(SiO4)3)
Red Garnet (Almandine-Pyrope series)
Garnet Group, Almandine (Fe3Al2(SiO4)3) or Pyrope (Mg3Al2(SiO4)3)
Plagioclase Feldspar
Plagioclase Feldspar Series (NaAlSi3O8 - CaAl2Si2O8)
Obsidian
Volcanic Glass (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Amethyst (Tumbled Quarz)
Silicon Dioxide (SiO2) with iron impurities
Quartz / Clear Quartz
Silicon Dioxide (SiO2)
Sandstone (with potential trace fossils)
Clastic sedimentary rock (primarily SiO2)
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Botryoidal Chalcedony (likely Desert Rose/Agatized Geode Crust)
Silicon Dioxide (SiO2)
Obsidian
Obsidian (Volcanic Glass)