Scientists Use Plastic To Create Lightweight 18-Carat Gold

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The new plastic gold closely resembles its metallic gold but it's much lighter (Credit: ETH Zurich/Peter Rüegg)

While jewelry crafted from gold can be gorgeous, even ardent fans will admit that wearing the heavy metal over long periods of time can get a little cumbersome and annoying. Now, researchers from Swiss university ETH Zurich have created a new form of lightweight gold that weighs five to ten times less than traditional 18-carat gold — which typically comprises 75 percent gold and 25 percent copper — but retains the same purity.

The researchers began by mixing gold nanocrystals with protein fibers, polymer latex, water, and salt to create a gel. They then replaced the water with alcohol and placed the gel inside a high-pressure carbon dioxide (CO2) chamber. The reaction between the gas and alcohol transformed the golden plastic into a light aerogel that could be heated to melt and mold into whatever form was needed. "This gold has the material properties of a plastic," says team leader Raffaele Mezzenga, professor of Food and Soft Materials at ETH Zurich.

A microscope image of gold nanoplatelets embedded in a latex matrix (Credit: Stephan Handschin/ScopeM/ETH Zurich)

In addition to being lighter, the "plastic" gold has other advantages over traditional forms. It can be melted into shape at about 105 degrees Celsius (221 degrees Fahrenheit), much lower than the 1,064 degrees Celsius (1,947 degrees Fahrenheit) required to melt pure 24-carat gold. The metal's firmness can be easily tweaked by changing the composition at the beginning of the process. It is also possible to vary the color by swapping the shape of the gold nanoparticles inside the matrix. For example, irregularly-shaped nanoplatelets will produce the conventional yellow shimmer, while spherical nanoparticles will result in gold with a violet hue. "As a general rule, our approach lets us create almost any kind of gold we choose, in line with the desired properties," says Mezzenga.

The researchers, who published their study in the journal Advanced Functional Materials on January 10, 2020, believe the new lightweight gold will be able to replace the metallic version in most traditional applications, including jewelry and watches. However, given that most buyers associate high-quality gold with weight, that may take some time. But the gleaming material will undoubtedly be beneficial for use inside electronic devices, chemical catalysts, and even radiation shielding.

Resources: newsatlas.com, phys.org, cnet.com

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142 Comments
  • hhay20485792
    hhay20485792Thursday, March 26, 2020 at 8:08 am
    all he did was drop it??
    • fudge05
      fudge05Thursday, March 26, 2020 at 7:54 am
      It sounds easy but also kind of difficult
      • dantdmroblox
        dantdmrobloxSaturday, March 21, 2020 at 8:46 am
        Does it mean you can microwave plastic to make gold???
        • fudge05
          fudge05Thursday, March 26, 2020 at 7:55 am
          No that is not even remotely close to what that means.
        • hunterxz11
          hunterxz11Friday, March 20, 2020 at 2:16 pm
          What sorcery is this
          • fudge05
            fudge05Thursday, March 26, 2020 at 7:56 am
            Good question, but if you really think about it it's not sorcery it's logic. You just have to be really smart
          • darkphantom358
            darkphantom358Thursday, March 19, 2020 at 2:17 pm
            You need special gold nanobites to make it
            • gamerkidjoe
              gamerkidjoeMonday, March 16, 2020 at 5:39 am
              I wonder how long it takes to make the gold
              • bobypandas123
                bobypandas123Thursday, March 12, 2020 at 7:24 am
                "it is so cool"
                • loveroflegos
                  loveroflegosTuesday, March 10, 2020 at 3:09 pm
                  so we can all be rich right
                  • texasrocks88
                    texasrocks88Sunday, March 22, 2020 at 4:21 pm
                    no we cant
                    • rand
                      randWednesday, March 11, 2020 at 12:55 pm
                      it would actually be less value
                    • griindz
                      griindzTuesday, March 10, 2020 at 10:25 am
                      to all the people who say just make a huge profit, just no, just, no, please god no, NO
                      • skeletron707
                        skeletron707Tuesday, March 10, 2020 at 7:27 am
                        cool i what to make gold like that