Purchased this coin last week and it arrived today. Got it relatively cheaply because of the encrustation behind
Augustus head obscuring the lettering. I promptly made a small container out of tin foil and added lemon juice. Placed the coin in for about 10 minutes and watched some bubbles rise. I rinsed it under running water using a nylon brush then repeated. After two lemon juice soakings the encrustation started breaking up nicely. I then brushed using liquid soap under running water and then back into lemon juice. I gave it about 6 lemon juice
baths each lasting about 10 minutes and then repeated the liquid soap and running water brushes. In about an hour it was done! I left small areas of encrustation in the lettering. One more soaking would probably get rid of it but I'm
fine with how it looks now.