• wolframhydroxide@sh.itjust.works
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            11 hours ago

            Zinc has a characteristic light bluish tint and oxidizes to white, not yellow or brown. Some of them appear slightly dull and oxidised with a grey or white layer.

            • FishFace@piefed.social
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              10 hours ago

              And how do you propose to know how blue-tinted those balls are without being able to tell what they’re reflecting and what the camera’s white balance is set to?

              I blurred the image and took a few colour samples; the balls are grey in the image, with very slightly more red in them than green or blue. That doesn’t mean they’re actually grey; they could be slightly blue and reflecting a slightly red scene or vice versa. They could be slightly green but the camera settings have “corrected” it to look grey.

              How can you tell that the “dull” ones are oxidised, as opposed to roughened, blurred due to movement or covered with some other substance like lubricant?

              • wolframhydroxide@sh.itjust.works
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                10 hours ago

                All excellent points! I concede to your deeper consideration. (Though I do think that a “roughened” ball bearing would rather prove my point for me, and that those which appear roughened are largely also those under other balls, lessening the chance that they are moving)

    • ilikecoffee@lemmy.world
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      1 day ago

      In general, metallic orthopedic implants are not affected by MRI.

      This isn’t an implant though. Massive difference.

      • toynbee@lemmy.world
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        24 hours ago

        I soon expect to have screws implanted in my spine. I also have other infirmities. I hope like hell to never have screws ripped through my vertebrae by an MRI.

        • ilikecoffee@lemmy.world
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          2 hours ago

          Usually titanium, but yeah sometimes medical stainless steel. Both are non-ferromagnetic, especially titanium. These balls look like they could well be normal steel or any other metal. Also, implants - unlike these metal balls - are usually screwed firmly into your bones. So yeah, implants should be mostly fine on MRI. Loose balls of dubious metal? Wouldn’t advise it. Keep in mind MRIs are literally powerful enough that metals in tattoo ink can even be an issue - which the article you linked mentions itself.