Been discussed numerous times .
Check out a product called " COIN CARE "
Gone up in Price like anything else .
A little shopping around can still find it
for around 15 dollars.
Honestly ( and I have used both ) Head
and shoulders above Verdi Care
Of course we all wish the old Blue Ribbon
coin conditioner was still around .
Other inexpensive solutions to try on Copper
or Bronze Coins
3 in 1 oil
Sewing machine oil
In fact any very light based oil used properly
in conjunction with a superb fine brush will yield
excellent results if done properly .