It has been designed and built by Australian coachbuilder Jim Frecklington who initiated the project himself, according to the Royal Collection Trust.
The project was backed by the Australian Government which donated £138,000, but it is understood that Frecklington met the rest of the cost himself.
It is the second coach Frecklington has built for the Queen – he built the Australian State Coach in 1988, and while that was commissioned and took 11 months to complete, the new self initiated coach was supposed to be completed in 2006 in time for the Queen’s 80th birthday.
For this reason the name of the coach has changed from Britannia to Diamond Jubilee State Coach.
The Royal Collection Trust, the arm of The Royal Household which collects, maintains and displays Royal objects, has acquired the Diamond Jubilee State Coach from Frecklington and plans to add it to the public display of coaches and carriages at the Royal Mews, Buckingham Palace, from 8 June.
At 5.5m long, over 3m high, and weighing over three tonnes, it requires three grooms and will be drawn by six horses.
The interior of the coach is lined with yellow silk and incorporates items donated by over 100 historic sites and organisations around Britain.
A spokeswoman for the Royal Collection Trust understands that Frecklington asked these organisations to contribute the artifacts.
Seat handrails are from the Royal Yacht Britannia, window frames and interior panels contain material from Caernarfon Castle, Canterbury Cathedral, Durham Cathedral, The Mary Rose (Henry VIII’s flagship), 10 Downing Street, and the Antarctic bases of Captain Scott and Sir Ernest Shackleton.
A British lead musket ball from the Battle of Waterloo and a piece of metal from the casting of the Victoria Cross have been incorporated.
Elsewhere a fragment of the Stone of Destiny, which has been used for centuries in the coronation of monarchs, is set into a panel below the seats.
The door to the carriage features an electric window – and is inlaid with diamonds and sapphires – while hydraulic stabilisers have been fitted to the underside of the carriage to cushion the ride.