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There are other uses for coins besides collecting. If used in a project you may want an attractive shine or a little bling. Look up penny bar tops where they shine half of the pennies before epoxying them in. I don't think it's fair to just shoot someone down if all you can present is your own narrow point of view. And to add to the topic you can also "paint" copper coins with ketchup to shine them up! Keep exploring, keep experimenting and keep learning. There are no mistakes, just unexpected outcomes to add to your knowledge.
Built two of these twenty years ago at 3'x4' with leftover 3/4" flooring for top and shelves. I may go out there and flip them over and steal your solution for putting wheels on.
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