I have a well-preserved Arab-Byzantine bronze with a nice red sand patina on it. Unfortunately it turns out it has bronze disease on parts of the edge (also a couple of small spots on the far side of the reverse that I somehow missed when I saw the listing). So now I would like to try to remove it all and keep it off while disturbing as little of the sand patina as possible. Anyone have any ideas on how I should go about doing this? Thanks.
If the BD isn't extensive, try mechanical debridement with a pick or brush and apply Verdicare; observe frequently after treatment.
Also, regarding that "red sand patina"... be sure that it isn't applied wax or something. There are a few dealers whose entire inventories have the same orange/yellow/red "patina"-- obviously something applied to the coins. I'd soak that coin in acetone, alcohol, and mineral spirits (one at a time) to see if the patina soaks off. If it is a true patina, none of those soaks should disturb it (don't rub them in the fluid, just soak).
what TIF said, i recently used that techniqe on this coin...note the little patch at the bottom. it's now being watched.