Reddit reviews Flintski Jewelry Sterling Silver US Quarter Coin Edge Coin Bezel Frame Mount 24.10mm x 1.70mm

This isn't silly or naive :) it is something important to you, and these are things that a jeweler could help you with.

The term I think you are probably looking for is "plated" rather than poured. A jeweler could put a very thin layer of gold on top of the metals; this would make them look like gold, add another layer of metal on top of them, and would allow all of the details show through. I have heard that chain is more difficult to plate than a solid object, because you have to be careful not to plate the links together. I haven't tried to plate chains myself, but I know that it is possible.

You didn't say if you were planning on wearing the quarter on the chain, or keeping them separately. If you did decide to make the quarter into a pendant, I might suggest putting a frame around it rather than drilling it. This way the quarter won't be damaged as much through wear. You could buy one online Like this one on amazon or have the jeweler make one for you.

All that said, there are a few rather blurry laws about defacing U.S. currency. Specifically it says that you cannot lower the value of a coin or bill intentionally or make it appear to be something other than what it is with malicious intent. That law shouldn't be an issue here, but some people may wonder about it a little and be hesitant to alter the coin in an official business setting. I'm not sure what you'll hear when it comes to plating the coin, but I don't really expect you to have any issues. :)

I am a little curious, if your main goal is to protect and preserve these items, why gold? Gold is pretty, valuable, and great to work with, but it is pretty soft and will wear off faster than some of the other metals you could plate it with. I only ask because you said so many times that it wasn't about the value of the gold. (though it is perfectly alright to just have a personal preference)