Just crunched some numbers on current prices for bronze and nickel in the US.. both not commonly consumed by recyclists locally that I know of.. and due to legal issues(not legal to deface coins).. I wanted to see how well the stuff held out against its face value of old..
Old 1965+ series(not the silvers)
1c = 3g = 34c bronze
2c = 4g = 45c bronze
5c = 2.5g = R1.25 nickel
10c = 4g = R2 nickel
20c = 6g = R3 nickel
50c = 9.5g = R4.75 nickel
R1 = 12g = R6 nickel
A set total = R17.79
Here is the real shocker.. if the known quantities was readily accepted for their minneral value.. they would be almost arguably be more practical space and weight wize.. apart from the 50c and R1 that are huge.. but the 20c is slightly larger than a R2 coin but packs R3..
So you could start a potential business buying nickel at 50c a gram.. melting and minting troy ounce bars or coins of fine nickel thats about R15.55 buy.. then sell at compettative rates.. the cheapest I can find on offer out there is R250 it seems.. thats more than what silver went for the first time I checked out bullion in 2004.. I dont know how popular this would be though.. you can always open at R15.50 and see what the willing go rate is.
Anyway.. that was fun.. dont throw those out yet.. happy hunting.