Vesicular Basalt with Secondary Mineral Infill
Mafic Volcanic Rock (Basalt)
Category
Browse mixed (igneous, sedimentary, metamorphic, and minerals) specimens identified by the Rock Identifier community.
Vesicular Basalt with Secondary Mineral Infill
Mafic Volcanic Rock (Basalt)
Kimberlite
Kimberlite
Snowflake Obsidian
Spherulitic Obsidian (primarily SiO2 with Cristobalite inclusions)
Mahogany Obsidian
Volcanic Glass (predominantly SiO2 with Fe2O3 inclusions)
Rhodonite
Rhodonite (MnSiO3)
Amethyst
Quartz variety; chemical formula: SiO₂ (silicon dioxide) with Fe³⁺ impurities
Green Aventurine
Silicon Dioxide (SiO2) with Fuchsite inclusions
Psilomelane (Manganese Ore)
Psilomelane (Ba,H2O)2Mn5O10
River Cobble (Basaltic/Andesitic)
Mafic Igneous Porphyritic Rock
Green Jasper
Silicon Dioxide (SiO2) with iron silicate inclusions
Chert Geode or Nodule
Microcrystalline Quartz (SiO2)
Ironstone Concretion (Ironstone Gourd)
Limonite/Goethite Concretion (FeOO(H))
Limonite Concretion
Hydrated iron(III) oxide-hydroxide (FeO(OH)·nH2O)
Geode (unopened)
Chert / Chalcedony Geode (SiO2)
Jasper
Silicon dioxide (SiO2) with impurities
Fossil Shell (Bivalve)
Class Bivalvia (Likely a member of the Ostreidae or Gryphaeidae family), CaCO3
Tree Agate
Silicon Dioxide (SiO2) - Dendritic Agate/Chalcedony
Orbicular Jasper (Eye Jasper / Kambaba-like pattern)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, SiO2)
Yellow Jasper
Jasper (Silicon Dioxide, SiO2)
Unakite (bottom) and Sodalite (top)
Epidotized Granite (Unakite) and Sodium Aluminum Silicate Chloride (Sodalite)
Greenstone
Metabasalt
Greenstone (Epidosite or Altered Basalt)
Epidosite (Ca2(Al, Fe)3(SiO4)3(OH))
Nephrite Jade
Ca2(Mg, Fe)5Si8O22(OH)2
Mica Schist
Mica Schist (predominantly composed of Muscovite or Biotite silicates)
Milky Quartz with Iron Staining
Quartz (Silicon Dioxide, SiO2)
Blue Calcite
Calcium Carbonate (CaCO3)
Sandstone
Sandstone (clastic sedimentary rock, composed predominantly of sand-sized minerals or rock fragments)
Green Fluorite
Fluorite (Calcium Fluoride, CaF2)
Sandstone (Quartzite-rich)
Clastic Sedimentary Rock (primarily SiO2)
Blue Lace Agate
Chalcedony (SiO2) with trace minerals
Granite
Granite (a felsic intrusive igneous rock)
Bumblebee Jasper (technically Bumblebee Stone)
Calcite, Aragonite, and Realgar/Orpiment mixture (SiO2 + CaCO3 + As2S3/As2S2)
Basalt (Greenstone)
Amygdaloidal Basalt / Chloritized Basalt
Basalt with Iron Oxidation
Mafic Igneous Rock (Basalt)
Milky Quartz Pebble
Silicon Dioxide (SiO2)
Marble
Recrystallized Calcite (CaCO3)
Serpentine
Serpentine group, including Antigorite, Lizardite, and Chrysotile (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4
Obsidian
Volcanic glass (SiO2-rich extrusive igneous rock)
Pyrite
Iron Sulfide (FeS2)
Quartz (Druzy) in host rock
SiO₂ (Silicon Dioxide) as Quartz, with unspecified host rock components (likely silicates and iron oxides)
Mica Schist
Medium-grade regional metamorphic rock (composition varies)