This post concerns the following three coins:
These coins are listed as having a “B” mintmark on the coin. I had trouble finding the “B” mintmark; its location isn't obvious (especially if you do not have any of the prior Edward VII issues to compare these to).
The mintmark is an incuse “B” on the crown where the center arch meets the headband.
I recommend adding a comment to the three web pages indicated above to indicate where the “B” mintmark is located on these coins.