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  2. Prices of chemical elements - Wikipedia

    en.wikipedia.org/wiki/Prices_of_chemical_elements

    This is a list of prices of chemical elements. Listed here are mainly average market prices for bulk trade of commodities. Listed here are mainly average market prices for bulk trade of commodities. Data on elements' abundance in Earth's crust is added for comparison.

  3. International Prototype of the Kilogram - Wikipedia

    en.wikipedia.org/wiki/International_prototype_of...

    The only three verifications occurred in 1889, 1948, and 1989. For instance, the US owns five 90% platinum / 10% iridium (Pt‑10Ir) kilogram standards, two of which, K4 and K20, are from the original batch of 40 replicas distributed in 1884. [Note 4] The K20 prototype was designated as the primary national standard of mass for the US. Both of ...

  4. Precious metal - Wikipedia

    en.wikipedia.org/wiki/Precious_metal

    One of the largest bullion coins in the world was the 10,000-dollar Australian Gold Nugget coin minted in Australia, which consists of a full kilogram of 99.9% pure gold. In 2012, the Perth Mint produced a 1-tonne coin of 99.99% pure gold with a face value of $ 1 million AUD, making it the largest minted coin in the world with a gold value of ...

  5. Iridium - Wikipedia

    en.wikipedia.org/wiki/Iridium

    Iridium in bulk metallic form is not biologically important or hazardous to health due to its lack of reactivity with tissues; there are only about 20 parts per trillion of iridium in human tissue. [22] Like most metals, finely divided iridium powder can be hazardous to handle, as it is an irritant and may ignite in air. [66]

  6. Platinum–iridium alloy - Wikipedia

    en.wikipedia.org/wiki/Platinum–iridium_alloy

    The international prototype of the kilogram (IPK) is an artifact standard of platinum–iridium alloy that was defined as having a mass of exactly one kilogram. Platinum–iridium alloys are alloys of the platinum group precious metals platinum and iridium. Typical alloy proportions are 90:10 or 70:30 (Pt:Ir).

  7. Platinum group - Wikipedia

    en.wikipedia.org/wiki/Platinum_group

    Naturally occurring platinum and platinum-rich alloys were known by pre-Columbian Americans for many years. [5] However, even though the metal was used by pre-Columbian peoples, the first European reference to platinum appears in 1557 in the writings of the Italian humanist Julius Caesar Scaliger (1484–1558) as a description of a mysterious metal found in Central American mines between ...

  8. Lists of countries by mineral production - Wikipedia

    en.wikipedia.org/wiki/Lists_of_countries_by...

    Complete list Aluminium [6] China India: List of countries by aluminium production: Bauxite [7] Australia Guinea: List of countries by bauxite production: Bismuth [8] China Vietnam: List of countries by bismuth production: Copper [9] Chile Peru: List of countries by copper production: Chromium [10] South Africa Turkey: List of countries by ...

  9. Talk:List of countries by iridium production - Wikipedia

    en.wikipedia.org/wiki/Talk:List_of_countries_by...

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