Hello all,new to the forum but not to collecting coins. I am new to the world of ancients though, so I'm sure I'll be posting regularly.
Picked up a lot of crusties after doing some research and deciding that's the way I wanted to go. Like the discovery aspect, and being able to learn about the coins as they slowly become clearer. Wanted to start with Greeks, but Romans were far cheaper.
All the coins in the lot were dirt clods with a faint outline of a head on 3-4 of them. The photos show the coins after about a week in and out of oil and hydrogen peroxide. Out of all the coins, one seems to be "done" to my eyes as it doesn't bubble anymore in the peroxide and no dirt is removed through scrubbing after the oil soak. All the rest still have dirt coming away after every scrubbing.

Curious about the condition on that one; it's the top coin by itself in the photo. The surface is rough, but nothing else will pick away (toothpicks) and it scrubs clean. Think I had an old penny with a similar "flakey" surface, but couldn't find it to compare.
Wondering what causes this or if it's common in old Roman coins of this nature?
I also assume the issues on the 2nd and 3rd coins (second row) are fairly common as well. One appears to have extra metal around the nose while the other... well, I don't know what happened to his face.
- tacked another larger photo below, been a while since I've posted coin photos

