After you try that, try boiling in hydrogen peroxide. That'll kill somebody if inhaled and do damage to the coin. (Seriously, do not do it.)
It might be interesting to try it, but the admonition to use distilled water (or deionized water - basically the same thing) is a good one. I can see it taking off lots of crud. Remember heat usually accelerates processes, a good rule-of-thumb is a doubling for each 10 degrees Celsius. So, lets see, room temp is 20 and boiling is 100 so you doubled it it 8 times which would be 2 to the eighth power, holy math Batman, that is like having it in water for a few years. Please take pictures before and after so we can see.
What, now? Boiling in hydrogen peroxide (at the concentration you're likely to have on hand) will give off oxygen and steam, period.
Inhaling too much oxygen can kill you too. Too much water can kill you as well. Too much of everything can pretty much kill you.
Originally Posted by Kentucky It might be interesting to try it, but the admonition to use distilled water (or deionized water - basically the same thing) is a good one. I can see it taking off lots of crud. Remember heat usually accelerates processes, a good rule-of-thumb is a doubling for each 10 degrees Celsius. So, lets see, room temp is 20 and boiling is 100 so you doubled it it 8 times which would be 2 to the eighth power, holy math Batman, that is like having it in water for a few years. Please take pictures before and after so we can see. Let's go through this slowly. For each 10 degree Celsius rise in temperature, the rate of change will double. Now we start off at room temperature (20 degrees Celsius) and go up to 100 degrees Celsius (where water boils at sea level). That makes a rise in temperature of 80 degrees Celsius. Now EACH 10 degree rise doubles the rate, so an 80 degree rise would double the rate 8 times (use your fingers if you have to). This would be 2 to the eighth power. So according to my calculator, this is a factor of 265 times, excuse me for my hyperbole. I still would like to see what happens.