MORE ON SULPHUR SPOTS Público Deposited

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  • The E-Sylum: Volume 7, Number 17, April 25, 2004, Article 22

    MORE ON SULPHUR SPOTS

    R.S. Neale writes: "While very true that carbon spots aren't
    carbon, I think that the writer of this commentary, admittedly
    not a chemist, should consult one to get his terminology
    straightened out. For example, when copper reacts with sulfur
    in some form or other, it becomes copper sulfide (not copper
    sulfate), and the process does indeed involve oxidation
    (wherein an element loses electrons to become a positively
    charged ion)."

    Joe Boling writes: "I believe most coin graders and conservators
    agree that "carbon spots" are usually the result of droplets of
    saliva (and an occasional dandruff flake) that have landed on
    coins while they were being handled and talked over. As such,
    I'm not sure that sulfur has any connection with them, though I
    don't know what the principal culprit would be. What's in
    saliva?"

    [What's in saliva probably depends on what the person was
    eating... -Editor]

URL da fonte Data de publicação
  • 2004-04-25
Volume
  • 7

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