Reserve Bank unveils a new coloured coin to commemorate the Anzac landings at Gallipoli.

One million of the country's first coloured coins will come into circulation next month to commemorate the centenary of the Anzac landings at Gallipoli.

The Reserve Bank of New Zealand and New Zealand Post today unveiled the new 50-cent coin at Government House in Wellington.

The coin, designed by New Zealand artist Dave Burke, will be available as legal tender to the public from March 23, and has been made to specifications that will be accepted in coin and vending machines.

Reserve Bank Governor Graeme Wheeler said the coin would circulate with existing currency and honoured the spirit of Anzac that was formed 100 years ago.

"This is the first time in New Zealand's history that we have had a colour commemorative circulating coin, and we expect it to be popular and highly sought-after," he said.

Governor-General Sir Jerry Mateparae said the coin represented the events of Gallipoli and was a symbol of our nationhood.

"It helps us to remember the New Zealanders who served there and all those who have served our country during times of conflict and peace, and it is evidence that the links with Australia and the Anzac spirit endure," he said.

NZ Post chief executive Brian Roche said it had commissioned Burke to design the coin as part of the company's five-year stamp and coin programme for the centenary of World War I.

He said the coin featured New Zealand and Australian soldiers standing back to back, with a white mangopare (hammerhead shark) pattern and silver fern.

The pattern symbolised strength and determination, while the silver fern represented the country's national identity.

The coins were minted and colour-stamped by the Royal Canadian Mint using world-first print pad technology.