annealed to for long periods. Telluric iron, which is an iron-nickel alloy very similar to meteorites, also displays very coarse Widmanstätten structures. Telluric iron is metallic iron, rather than an ore (in which iron is usually found), and it originated from the Earth rather than from space. Telluric iron is an extremely rare metal, found only in a few places in the world. Like meteorites, the very coarse Widmanstätten structures most likely develop through very slow cooling, except that the cooling occurred in the Earth's mantle and crust rather than in the vacuum and microgravity of space. Such patterns have also been seen in mulberry, a ternary uranium alloy, after aging at or below for periods of minutes to hours produces a monoclinic ɑ phase. However, the appearance, the composition, and the formation process of these terrestrial Widmanstätten structures are different from the characteristic structure of iron meteorites. When an iron meteorite is forged into a tool or weapon, the Widmanstätten patterns remain but become stretched and distorted. The patterns usually cannot be fully eliminated by blacksmithing, even through extensive working. When a knife or tool is forged from meteoric iron and then polished, the patterns appear on the surface of the metal, albeit distorted, but they tend to retain some of the original octahedral shapes and the appearance of thin lamellae crisscrossing each other. Pattern-welded steels such as Damascus steel also bear patterns, but they are easily discernible from any Widmanstätten pattern. See also Acicular ferrite Count Alois von Beckh Widmanstätten Glossary of meteoritics Meteorite References External links Widmannstätten figures on the Gibeon Iron-Meteorite Meteorite mineralogy and petrology Patterns