Initially, British and Australian coins circulated in New Zealand. The devaluation of the New Zealand pound relative to sterling in the 1930s led to the issue of distinct New Zealand coins in 1933, in denominations of 3d, 6d, 1s, 2s (the florin) and 2½s (the half-crown), minted in 50% silver until 1946 and in cupro-nickel from 1947. In 1940, bronze ½d and 1d coins were introduced. All these denominations were the same size and weight as their equivalents in the Australian and UK coinage (although Australia never minted the half-crown).
According to Encyclopaedia of New Zealand 1966, the original specifications for the coin were (in measurement units of the time):
Diameter of Coin: 0.765 inches
Standard Weight: 43.63636 grains
Remedy Allowance (margin of error in weight): 0.346 grains
In regards to statistics, it has to be noted that the mintage figures provided by the Reserve Bank of New Zealand include, in some cases (like the 1953 mintages), the proof issue of the year while in most other cases they do not.
According to the Reserve Bank of New Zealand, the total mintage of the denomination during its existence was 59,547,364 (60 mln).
Counting the (few) known proof mintages, the total mintage adds up to 59,572,434 (60 mln).
Of them, 18,340,404 (18 mln) were silver and 41,232,030 (41 mln) were cupronickel.
The sixpence, shilling, and florin (2 shilling), although rarely seen in circulation, remained legal tender as late as 2006, being used as the identical size and value of its decimal successors: the 5c (cents), 10c, and 20c coins respectively. They were demonetised on 31 October 2006, when the 5c coin and the original 10c and 20c coins were withdrawn from circulation.
Effigy of the monarch, legend.
During the existence of the denomination, ruling monarchs for whom sixpence coins were minted were King George V, King George VI and Queen Elizabeth II. No coins were minted for King Edward VIII during his short reign.
After the Independence of India in 1947, the title "Emperor" was dropped from the legend of King George VI.