Homebrew PCBs

Dave,
Where have you been? Don't you know that we use copper plated zinc 
pennies?  And that eating a copper penny is not considered a hazard, but 
the zinc coated ones are?  I guess the acids in your stomach either 
don't dissolve copper, or it requires a lot of copper to be a problem. 
 Otherwise, lead killed the Roman Empire, but copper will have killed a 
_bunch_  of modern countries.
Does anyone know why aluminum is bad for house wiring?  (real question, 
not a joke)  Is it that aluminum has a greater thermal expansion ratio 
than copper, and so the connections worked themselves apart?
Thanks
Richard

>But, I'm thinking that here in the US, we use copper pennies and 
>copper water pipe so we probalby dump more copper into the waste 
>stream than all the pcb houses put togehter.
>
>Dave
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