I love "all" ancient coins, so again => congrats on snagging a 2000 year old piece of awesome, my new coin-friend!! Oh, and I always applaud the efforts of the coin-cleaners, but yah, I have never bothered trying to clean one of these coins (or do my own wiring in my house, or tuning my truck's engine, or doing my own dentistry, etc) ... I usually leave these chores which lie outside of my wheelhouse to others who seem to be efficient and eager ... => yah, sometimes it's a no brainer!!
@Amos 811 Other than a few patches of earthen crud on the obverse, it looks to me like you're already down to porous metal surfaces.
Life has become so specialized. Unfortunately, most things are "outside my wheelhouse" anymore and I have not been called "efficient and eager" for decades. I once did receive praise on an Army efficiency report where I was called a "highly conscious soldier" but the Commanding Officer correctly surmised that the guy that wrote it was the victim of a new invention called spellcheck. I do clean 'at' some coins but not all of them benefit from the experience. I prefer to concentrate my efforts in other fields of numismatics. I suggest you select the area that fits you best.
So I guess you were not caught asleep on duty. Yep. If I look back on my Officer's Efficiency Reports, it no longer resembles the tech idiot sitting in front of this computer trying to figure out how it works.
After reading that, how much of a discount would you say is appropriate to ask for a coin known to have bronze disease?
Wow...that's a hard question, it would depend on two things 1) mainly how far the bronze disease had spread - if it is extensive, the coin is damaged beyond repair and 2) the rarity - rare coins would still have value as long as they are recognizable.