Blood Money :~)))))

Try a little rubbing alcohol.

The coin has 10 % copper so I would not use acids or caustics or peroxides

I would try first soaking it in pure distilled water for 24 hours

If that leaves stains I would try pure acetone in a well ventilated room dip it in acetone for 10 minutes and it will flash dry

If this does not help what I usually do is hold the coin under flowing water for several minutes and to avoid the white water stains upon drying put it immidiately in acetone swirl it for a minute and then let flashdry

Bonne Chance

The blood has dried as this has happened a few months ago..... Thanks Jim one off ebay I think I paid 50 for it not too bad for 7 Grams odd