On the New Zealand coins above the year and below the queen there are the letters "IRB" what do they mean?

-Any one know what those letters mean and why they are there? Googling didn't tell me anything so wondering what people think



http://www.keyimagery.com/media/members/鈥?/a>The same appears on Australian coins, underneath the effigy of Queen Elizabeth and they are the initials of the sculptor who designed it, Ian Rank-Broadley - see links below.



http://en.wikipedia.org/wiki/Ian_Rank-Br鈥?/a>



http://www.ianrank-broadley.co.uk/Generally letters on coins are the initials of the designer which is a concession to recognise their work.