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  2. Environmental impact of iron ore mining - Wikipedia

    en.wikipedia.org/wiki/Environmental_impact_of...

    Hematite and magnetite are the most common types of Iron ore. Roughly 98% of iron ore on the global market is used in iron and steel production. [8] The other 2% of iron ore is used to make powdered iron for certain types of steel, auto parts, and catalysts; radioactive iron for medicine; and iron blue in paints, inks, cosmetics, and plastics. [5]

  3. Metallurgy in pre-Columbian America - Wikipedia

    en.wikipedia.org/wiki/Metallurgy_in_pre...

    Lumps of iron pyrite, magnetite, and other materials were mostly shaped into mirrors, pendants, medallions, and headdress ornaments for decorative and ceremonial effect. [32] However, concave iron ore mirrors were apparently used for firing and optical purposes by the Olmec (1500–400 BCE) and Chavin (900–300 BCE) cultures, [33] and ilmenite ...

  4. Iron ore - Wikipedia

    en.wikipedia.org/wiki/Iron_ore

    Elemental iron is virtually absent on the Earth's surface except as iron-nickel alloys from meteorites and very rare forms of deep mantle xenoliths.Although iron is the fourth most abundant element in Earth's crust, composing about 5% by weight, [4] the vast majority is bound in silicate or, more rarely, carbonate minerals, and smelting pure iron from these minerals would require a prohibitive ...

  5. Supergene (geology) - Wikipedia

    en.wikipedia.org/wiki/Supergene_(geology)

    Supergene enrichment occurs at the base of the oxidized portion of an ore deposit. Metals that have been leached from the oxidized ore are carried downward by percolating groundwater, and react with hypogene sulfides at the supergene-hypogene boundary. The reaction produces secondary sulfides with metal contents higher than those of the primary ...

  6. Ferrous metallurgy - Wikipedia

    en.wikipedia.org/wiki/Ferrous_metallurgy

    Iron meteorites consist overwhelmingly of nickel-iron alloys. The metal taken from these meteorites is known as meteoric iron and was one of the earliest sources of usable iron available to humans. Iron was extracted from iron–nickel alloys, which comprise about 6% of all meteorites that fall on the Earth.

  7. Arsenical bronze - Wikipedia

    en.wikipedia.org/wiki/Arsenical_bronze

    There are few real advantages metallurgically for the superiority of tin bronze, [1] and early authors suggested that arsenical bronze was phased out due to its health effects. It is more likely that it was phased out in general use because alloying with tin gave castings which had similar strength to arsenical bronze but did not require ...

  8. Iron-rich sedimentary rocks - Wikipedia

    en.wikipedia.org/wiki/Iron-rich_sedimentary_rocks

    Iron formations can be divided into subdivisions known as: banded iron formations (BIFs) and granular iron formations (GIFs). [ 3 ] The above classification scheme is the most commonly used and accepted, though sometimes an older system is used which divides iron-rich sedimentary rocks into three categories: bog iron deposits , ironstones , and ...

  9. Extractive metallurgy - Wikipedia

    en.wikipedia.org/wiki/Extractive_metallurgy

    Extractive metallurgy is a branch of metallurgical engineering wherein process and methods of extraction of metals from their natural mineral deposits are studied. The field is a materials science, covering all aspects of the types of ore, washing, concentration, separation, chemical processes and extraction of pure metal and their alloying to suit various applications, sometimes for direct ...