Hugh Jefferies, editor of Gibbons Stamp Monthly, called the first-class postal flub "embarrassing," adding that "whoever designed this will have egg on their face and someone's head will roll."
The stamps are worth a total of 5.80 NZ dollars, but Ms. Middleton's half is priced slightly lower at 2.40 NZ dollars than Prince William's side, which costs 3.40 NZ dollars. The value will most likely increase, though, now that the commemorative memento has turned into an instant collectors' item.
This isn't the first mail mishap. The Australian Royal stamp celebrating Prince Charles and Diana had been criticized because it presented the couple facing away from each other.
And although the Queen, who is New Zealand's head of state, has to approve all stamp designs, this Prince William and Kate's version may have received the Buckingham Palace OK before the center break was added, Jefferies speculated.
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