Hi I just finally purchased a scale and am not sure what explains this but 3 1969 50 cent Coins are a gram difference there all 1969 one is 8.gm next 8.10 and 8.20/21 why is this i can see maybe a point or 2 off but that me
Struck on a thicker Planchet. There is a exact weight, then there is a +/- tolerance in weight for all coins. Yours does not have that much of a difference.
And there isn't a gram difference just .2 grams I don't know what the spec were for the Canadian half, but the specs for a US half dollar for that year was +/- .4 grams, a possible spread of .8 grams. So I would say there is a very good chance you are just seeing normal weight variation and that all of them are within spec.