Safi - 24-48 hrs in each: DW, Acetone, and Xylene. Sodium Sesquicarbonate is driven by metal, build-up, and past experiences. This particular restoration saw 6 hours in a 2.5% solution and then another 4 hours in a 1% solution. There is a blog post in my signature if interested.
I could probably take this a bit further at a low ratio but I'm happy with where it is at. Not that I would ever have it graded but, I see no reason it would detail as is for cleaning.
I swing a metal detector and have a knack for finding dirty old coins.
Dirt coin restoration projects -
https://www.prodetecting.com/restorationsDirt coin restoration blog -
https://www.prodetecting.com/blog/ccawDirt coin dig videos -
https://www.youtube.com/@prodetecting