Our Attempts At Cleaning So Far

You are being much more patient than I ever was. I no longer clean coins finding that it's just not for me. If I had your coins, I would be so frustrated they would have been in my slugs pile already. You, at least, are making progress and I applaud you for that. IMHO the coins you have posted will not clean up very well. There seems to be a lot of corrosion that has eaten away at the metal leaving very little to identify. Good luck and keep posting your progress. I amy not be very good at cleaning, but at least I find your efforts interesting to follow.

You can get a soft bristled brass brush over at ancient forvm or NRC for 5 bucks or so. In my experience they help knock off some of the top layer of grit and help get things going, you just don't want to brush very hard or for very long - and I only do it under running water but I forget who told me to do that. I admire your patience and restraint, some of those look like they will clean up nicely.

when the coin is under the microscope I put a drop or 2 or peroxide on the coin for about 5 minutes, wipe, brush and have another scrape before putting back into the oil

AS far as cleaning is concerned, discretion rather than valour may be better applied at this point. So far I think you have done really well with them.

It is my opinion that these coins have sustained corrosion before you ever got to them. I do not think that extra chemical cleaning will help.

The next step will require considerable patience and skill. Picking at them now using an orange stick, and vision assisted with a loupe, seems to be the next move.

Do a screen dump of the pictures you have taken to assist.

I like the theory, but from my experience, it was a disaster.

I tried that once. I heated a late Roman bronze to the point where I could just handle it with my fingers, then plunged it into cold water.

The result?

The coin just broke up into a jillion little particles.

The metal for a coin comes out of the ground. That is exactly where the result of my little experiment ended up.
"From dust to dust, ashes to ashes."

I really do not think heating / cooling, OR cooling / heating with ancient copper silver or bronze coins is a good idea. I found out the hard way.

From what I can surmise, there is a great probability that corrosion products at least to a minor extent, can effuse themselves right through the body of a bronze coin. If that has in fact happened during the last 1600 years or more, and you attempt to heat or cool it, there is a very risk of disaster, as I found out for myself.

You just have no way of knowing the extent of chemical degradation of the body of the coin before you start heating or cooling it.

Degradation of the body of ancient silver coins has a different cause. Quite often after an ancient silver coin is struck, a very slow natural crystallisation process can start, which affects the whole body of the coin. This is why some ancient silver coins are chipped. I would imagine that an ancient silver coin that is subjected to severe cooling or heating may spontaneously break up as well.

I certainly would NOT contemplate the risk.

WOW it broke on the carpet?!! I would have been both shocked and devastated. In my experience of heating ancient bronze coins, I have done it a few times in the oven @ 450 degrees, Out of the 20 or so coins that I have finally made it to the baking process, I lost 4. One crumbled in my hand, the others just cracked and the metal began to flake off in clumps. Not a good idea- this process should be avoided, unless you are treating bronze disease on a small effected area. IMHO.