Serpentinite
Serpentinite (containing minerals of the Serpentine subgroup: Antigorite, Lizardite, and Chrysotile; formula (Mg,Fe)3Si2O5(OH)4)
Category
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Serpentinite
Serpentinite (containing minerals of the Serpentine subgroup: Antigorite, Lizardite, and Chrysotile; formula (Mg,Fe)3Si2O5(OH)4)
Petrified Wood
Silicified Wood (SiO2)
Labradorite
Labradorite (a variety of Plagioclase Feldspar), Na(AlSi3O8) to Ca(Al2Si2O8)
Labradorite (likely Black Labradorite or Larvikite)
Labradorite (Na,Ca)(Al,Si)4O8. If a rock, it is typically anorthosite, gabbro, or norite, or a variety of syenite called Larvikite if it is specifically from Larvik, Norway.
Jade (likely Nephrite or Jadeite)
Nephrite (a variety of actinolite, Ca2(Mg,Fe)5Si8O22(OH)2) or Jadeite (NaAlSi2O6)
Yellow Chalcedony
Chalcedony (a cryptocrystalline variety of Quartz, SiO₂)
Ferruginous Quartz (Carnelian-tinted Quartz)
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Mica Schist
Foliated Metamorphic Rock (rich in Muscovite or Biotite)
Granite
Phaneritic plutonic rock (SiO2 typically >69%)
Granite Gneiss
Gneiss (High-grade regional metamorphic rock)
Quartz
Silicon dioxide (SiO₂)
Basalt
Basalt (dominated by plagioclase feldspar and pyroxene)
Sandstone (likely Arkosic or Quartzose)
Sandstone (SiO2 with inclusions)
Sandstone
Sandstone (lithified arenite/wacke)
Quartz (Iron-stained or Ferruginous)
Silicon Dioxide (SiO2)
Manganese Oxide Crust on Limestone
Manganese Oxides (e.g., Pyrolusite MnO2 or Romanechite) on CaCO3
Turquoise
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Sandstone (likely Arkosic)
Clastic Sedimentary Rock (primarily SiO2 with Feldspar)
Petrified Wood
Silicified Wood (primarily SiO2 - Silicon Dioxide / Chalcedony)
Granite Pebble
Granite (Phaneritic intrusive igneous rock comprising Quartz, Feldspar, and Mica)
Clear Quartz Crystal
Quartz (Silicon Dioxide, SiO2)
Chert
Chert (microcrystalline quartz)
Almandine Garnet in Schist
Almandine Garnet (Fe3Al2(SiO4)3) in Mica Schist
Concretion (Sandstone)
Carbonate-cemented Sandstone Concretion
Granite
Intrusive igneous rock (Acidic)
Goethite (likely as part of Limonite/Ironstone)
Goethite (α-FeOOH)
Basalt with Quartz/Calcite Veins
Amygdaloidal Basalt (SiO2 or CaCO3 inclusions)
Banded Gneiss
Gneiss (pronounced "nice")
Bauxite
Bauxite (Al2O3·nH2O)
Fossiliferous Chert (with Brachiopod or Mollusk fragments)
Silicon dioxide (SiO2) with Calcium Carbonate (CaCO3) inclusions
Citrine
Citrine (Silicon Dioxide - SiO2)
Black Obsidian
Volcanic Glass (predominantly SiO2, Silicon Dioxide)
Quartz Druze on Matrix
Silicon Dioxide (SiO2)
Corundum
Corundum (Al2O3)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Quartzite
Quartzite (primarily Silicon Dioxide, SiO2)
Basalt with Weathering Crust
Extrusive mafic volcanic rock
Tiger's Eye
Tiger's Eye (a variety of Quartz, SiO₂)
Granite
Granite (Felsic Plutonic Rock)
Jade
There are two distinct minerals commonly known as Jade: Nephrite (a calcium magnesium silicate - Ca2(Mg,Fe)5Si8O22(OH)2) and Jadeite (a sodium aluminum silicate - NaAlSi2O6). Based on the image showing a typically softer, more fibrous appearance, it is likely Nephrite.
Smoky Quartz
Silicon Dioxide (SiO2)
Lapis Lazuli
Lazurite-dominant rock, (Na,Ca)8(AlSiO4)6(SO4,S,Cl)2