Please note: It is very easy to clean Ancient Coins, just look at the picture below. PRESERVING them is another matter. You can take any coin to its base metal. You don't need to read any further if that is your goal. Just soak them in battery acid.... if your thinking you might want to have something a little nicer than that... well now you are at the right spot.
But let me warn you. Cleaning Ancient Coins is more an art than a science. And it is like politics when you are discussing how to clean coins. So, welcome... hope you have as much fun as I have and still do. Good Luck!