Japan: 1/2 sen y16?

Hi,

I have 3 of these coins, but the physical proportions are all different!

1. y16.1 Meiji era 10 W, grade F  : weight 3.16gr, diameter 22.15mm, thickness 1.13mm
2. y16.2 Meiji era 17 W, grade F  : weight 2.97gr, diameter 22.01mm, thickness 1.14mm
3. y16.2 Meiji era 19 W, grade VF  : weight 3.54gr, diameter 21.91mm, thickness 1.40mm

1:

2:

3:

Personnally I find the deltas a bit too high even taking the grades (mine) into account, what do you think?

Ole

I still think that the variation is within reason.... especially after taking the grades into account