Dendritic Agate
Silicon Dioxide (SiO2) with inclusions
Category
Browse mineral like biological tissue specimens identified by the Rock Identifier community.
Dendritic Agate
Silicon Dioxide (SiO2) with inclusions
Granite
Granite
Yellow Aventurine (specifically a carved crescent moon)
Silicon Dioxide (SiO2) with inclusions
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily SiO2)
Septarian Nodule (Dragon Stone)
Septarian Concretion (CaCO3 with Siderite and Calcite)
Geode (Quartz)
Silicon Dioxide (SiO2)
Biotite Mica
K(Mg, Fe)3AlSi3O10(F, OH)2
Amygdaloidal Basalt
Basalt with secondary mineral infilling
Tree Agate (Dendritic Agate)
Silicon Dioxide (SiO2) with Manganese/Iron inclusions
Bauxite
Bauxite (Al(OH)3, AlO(OH))
Obsidian
Volcanic glass
Petrified Wood
Silicified Wood (primarily SiO2 - Silicon Dioxide)
Red Sandstone
Arenite (high iron oxide content)
Biotite Mica
Biotite (K(Mg,Fe)3AlSi3O10(OH,F)2)
Sandstone
Sandstone (clastic sedimentary rock, predominantly SiO2)
Schist
Mica Schist
Quartzite with Hematite staining
Quartzite (SiO2) with iron oxide inclusions
Druzy Chalcedony/Quartz on Fluorite core
Silicon Dioxide (SiO2) on Calcium Fluoride (CaF2)
Quartz on Schist
Silicon Dioxide (SiO2) on Foliated Metamorphic Rock
Conglomerate
Conglomerate rock
Amethyst or Smoky Quartz Geode Slice
Crystalline Silicon Dioxide (SiO2) with iron impurities
Fossil Coral (Favosites)
Favosites (Order: Tabulata, Phylum: Cnidaria)
Blue Apatite
Apatite (Calcium Phosphate) - Ca5(PO4)3(F,Cl,OH)
Basalt
Mafic volcanic rock (primarily plagioclase feldspar and pyroxene)
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic volcanic rock)
Dendritic Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with inclusions
Mica Schist
Mica Schist (predominantly Muscovite or Biotite sheet silicates)
Amygdaloidal Basalt
Amygdaloidal Mafic Volcanic Rock (Basalt)
Gneiss
High-grade regional metamorphic rock (Foliated)
Gneiss (Metamorphic Rock)
Gneiss
Concretion (Sandstone)
Sandstone Concretion
Mica Schist
Mica Schist (predominantly Muscovite or Biotite sheet silicates)
Biotite Mica in Host Rock
Biotite (K(Mg,Fe)3AlSi3O10(F,OH)2)
Biotite Schist
Biotite-rich Schist (K(Mg,Fe)3AlSi3O10(OH,F)2)
Limonite-stained Granite
Felsic Plutonic Rock with Hydrated Iron Oxides
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 inclusions)
Ferruginous Quartz (Iron-Stained Quartz)
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Blue Sapphire
Corundum (Al2O3 with trace Titanium and Iron)
Obsidian
Obsidian (volcanic glass; primarily SiO2)
Mahogany Obsidian
Obsidian (Volcanic Glass) with Hematite/Magnetite inclusions
Azurite
Azurite (Cu3(CO3)2(OH)2)
Pyrite in Quartz
Iron Sulfide (FeS2) in Silicon Dioxide (SiO2)