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Metamorphic Pelitic Rock
Category
Browse man made object (simulant) specimens identified by the Rock Identifier community.
Slate
Metamorphic Pelitic Rock
Quartzite
Metamorphic Quartzite (SiO2)
Chalcedony (Agate / Jasper Specimen)
Silicon Dioxide (SiO2)
Fossilized Coral (Petoskey Stone / Hexagonaria)
Hexagonaria percarinata / Rugosa coral (CaCO3)
Chert / Flint
Silicon Dioxide (SiO2)
Brecciated Jasper
Brecciated Jasper (Microcrystalline Quartz / SiO2)
Green Aventurine
Silicon Dioxide (SiO2+KAl2(AlSi3O10)(OH)2)
Gabbro
Gabbro (Mg, Fe)2Si2O6 / (Ca, Na)(Al, Si)4O8
Granite
Granite (composed primarily of Quartz, Feldspar, and Mica)
Chert (with Quartz)
Microcrystalline Quartz (SiO2)
Chert (Chalcedony/Agate variety)
Silicon Dioxide (SiO2)
Diamond (in Jewelry)
Carbon (C)
Tumbled blue-green stone, likely chrysocolla or dyed chalcedony
Probable chrysocolla (hydrated copper aluminosilicate; variable composition), though appearance could also represent dyed chalcedony
Hag Stone
Perforated Sedimentary Rock (Typically Limestone or Sandstone)
Bog Iron / Limonite Concretion
Goethite/Limonite mixture (FeO(OH)·nH2O)
Turquoise
Hydrated phosphate of copper and aluminium: CuAl6(PO4)4(OH)8·4H2O
Petoskey Stone / Rugose Coral Fossil
Hexagonaria percarinata
Likely blue glass or synthetic gemstone jewelry
Uncertain; possibly synthetic spinel, cubic zirconia, or blue glass
Fossil Coral
Scleractinia (Stony Coral) fossil
Red Sandstone
Quartz Arenite (iron-stained) / SiO2
Quartzite
Metamorphic Quartzite (SiO2)
Quartzite
Metamorphic Rock (Mainly SiO2)
Lapis Lazuli
A metamorphic rock primarily composed of lazurite (Na,Ca)8[(S,SO4,Cl)2|(Al6Si6O24)], calcite (CaCO3), and pyrite (FeS2).
Tumbled carnelian/chalcedony
Cryptocrystalline quartz, SiO₂ (iron-bearing chalcedony)
Agate
Silicon Dioxide (Chalcedony), SiO2
Jasper
Silicon Dioxide (SiO2), microcrystalline quartz
Green Aventurine
Quartz (SiO2) with fuchsite inclusions
Petrified Wood
Silicified wood / Permineralized wood (SiO2)
Agate
Silicon dioxide (Chalcedony), SiO2
Labradorite (Tumbled)
Plagioclase Feldspar (Na,Ca)(Al,Si)4O8
Agate
Silicon Dioxide (Chalcedony), SiO2
Jasper
Silicon Dioxide (Microcrystalline Quartz, SiO2)
Agate
Silicon dioxide (Chalcedony), SiO2
Jasper
Microcrystalline Quartz (SiO2)
Jasper
Microcrystalline Quartz (SiO2)
Jasper
Microcrystalline quartz (SiO2)
Quartz
Silicon Dioxide (SiO2)
Green Jasper
Microcrystalline Quartz (Chalcedony), SiO2
Jasper
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Red Jasper
Microcrystalline Quartz (Chalcedony), SiO2
Quartz with Matrix
Silicon Dioxide (SiO2)
Green Aventurine
Quartz variety (SiO2) with fuchsite inclusions