Penny Mosaic Warning

We regularly see questionable information online concerning how to mosaic and how to do other art and craft projects. Mostly this information is questionable because it was written without regard to durability or how the project could have been used as an opportunity to make real art (personal, unique) instead of making clones of something already mass produced. Sometimes we even see instructions that are potentially dangerous or even likely to be dangerous. The recent fad of tiling floors with copper pennies may be an example of this, at least in certain situations.

In micro amounts, copper is a nutrient and is found in all plant and animal life. On the other hand, excessive exposure to copper can be toxic, particularly if a person has a genetic predisposition to a condition called Wilson’s Disease, in which the liver is unable to remove excess copper from the body.

Sure we all handle copper pennies every day, but this is different from lining a living space with them, especially on a floor where foot traffic will abrade the pennies and household cleaners will accelerate the forming of copper oxides and other toxic compounds.

Different websites mention coating the pennies with urethanes and other sealers prior to use. That is probably good in theory, but I’m not confident that the thin layer of sealant will isolate the copper for very long under normal use conditions. Keep in mind that copper is fairly soft and fairly reactive. What is acceptable for a wall or a mosaic sculpture is often inadequate for a floor.

4 thoughts on “Penny Mosaic Warning

  1. Jim Sylvester

    I would suggest using pennies after 1982 if you are concerned about possible copper exposure. Post 1982 pennies constain no copper due to the cost of copper exceeding the valve of the coin.

    Reply
    1. Joe Moorman Post author

      Those pennies DO contain copper. The entire surface is copper. Only the internal material is zinc.

      Reply
      1. Jim Sylvester

        You are correct, pre 82 have are 95% copper. Post 82 are 2.5% copper, still a better choice if you are considered with copper exposure. I would also suggest you have your punbling inspected copper pipes for water delivery is code in most states.

        Reply

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