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  2. Evolution of metal ions in biological systems - Wikipedia

    en.wikipedia.org/wiki/Evolution_of_Metal_Ions_in...

    The Earth began as an iron aquatic world with low oxygen. The Great Oxygenation Event occurred approximately 2.4 Ga (billion years ago) as cyanobacteria and photosynthetic life induced the presence of dioxygen in the planet's atmosphere. Iron became insoluble (as did other metals) and scarce while other metals became soluble.

  3. Three-age system - Wikipedia

    en.wikipedia.org/wiki/Three-age_system

    Jōmon pottery, Japanese Stone Age Trundholm sun chariot, Nordic Bronze Age Iron Age house keys Cave of Letters, Nahal Hever Canyon, Israel Museum, Jerusalem. The three-age system is the periodization of human prehistory (with some overlap into the historical periods in a few regions) into three time-periods: the Stone Age, the Bronze Age, and the Iron Age, [1] [2] although the concept may ...

  4. Iron in biology - Wikipedia

    en.wikipedia.org/wiki/Iron_in_biology

    The ability of sea mussels to maintain their grip on rocks in the ocean is facilitated by their use of organometallic iron-based bonds in their protein-rich cuticles. Based on synthetic replicas, the presence of iron in these structures increased elastic modulus 770 times, tensile strength 58 times, and toughness 92 times. The amount of stress ...

  5. Ferrous metallurgy - Wikipedia

    en.wikipedia.org/wiki/Ferrous_metallurgy

    Cast iron development lagged in Europe because wrought iron was the desired product and the intermediate step of producing cast iron involved an expensive blast furnace and further refining of pig iron to cast iron, which then required a labor and capital intensive conversion to wrought iron.

  6. Allotropes of iron - Wikipedia

    en.wikipedia.org/wiki/Allotropes_of_iron

    Below 912 °C (1,674 °F), iron has a body-centered cubic (bcc) crystal structure and is known as α-iron or ferrite. It is thermodynamically stable and a fairly soft metal. α-Fe can be subjected to pressures up to ca. 15 GPa before transforming into a high-pressure form termed ε-Fe discussed below.

  7. Meteoric iron - Wikipedia

    en.wikipedia.org/wiki/Meteoric_iron

    The bulk of meteoric iron consists of taenite and kamacite.Taenite is a face-centered cubic and kamacite a body-centered cubic iron-nickel alloy.. Meteoric iron can be distinguished from telluric iron by its microstructure and perhaps by its chemical composition also, since meteoritic iron contains more nickel and less carbon.

  8. Puddling (metallurgy) - Wikipedia

    en.wikipedia.org/wiki/Puddling_(metallurgy)

    The best yield of iron achievable from dry puddling is one ton of iron from 1.3 tons of pig iron (a yield of 77%), but the yield from wet puddling was nearly 100%. The production of mild steel in the puddling furnace was achieved circa 1850 [ citation needed ] in Westphalia , Germany and was patented in Great Britain on behalf of Lohage, Bremme ...

  9. Banded iron formation - Wikipedia

    en.wikipedia.org/wiki/Banded_iron_formation

    Banded iron formation from the Barberton Greenstone Belt, South Africa. A typical banded iron formation consists of repeated, thin layers (a few millimeters to a few centimeters in thickness) of silver to black iron oxides, either magnetite (Fe 3 O 4) or hematite (Fe 2 O 3), alternating with bands of iron-poor chert, often red in color, of similar thickness.