I don’t like using proprietary products because I don’t know what’s in them, and I believe VerdiCare is difficult to obtain in the UK anyway. After some research on what the British Museum used to use to treat bronze disease and verdigris on large objects, like cannon, I tried the technique for myself on this battered 1799 half-penny.
For anyone interested, the treatment was 100 minutes at 90°C in a 2% w/w solution of sodium sesquicarbonate in chlorine-free water. Followed by a rinse in chlorine-free water to remove the chemical and then a rinse in acetone to remove the water. The heat is needed as the reaction is impossibly slow at room temperature.