Mr Baker said the carriage was exquisite and everything for it had to be perfect. The handles had taken him 30 hours to make.
"That was the biggest challenge to keep [the stones] looking beautiful and blue in the background without them falling out." Each individual stone had a claw over it to attach it to the metal. "You couldn't really put a price on them to be honest. The hours and the work that went into them - the actual gold plating on them was just amazing."
His brother Les Baker, whose paint-making firm Norglass provided 10 products for the coach, said it was magnificent and held more than 100 artefacts from all over the world.
"It's not just a coach ... It's really a mobile time capsule."
The three-tonne coach, designed and built by Australian Jim Frecklington, had been planned for the Queen's 80th birthday in 2006 but fell victim to delays and a shortage in funding. The Royal Collection Trust purchased it and flew it from Australia to Britain in 2012.
The Diamond Jubilee state coach exudes luxury, with the seats made from Sudbury gold silk brocade, aircraft-grade aluminium wheels and armrests made from the former royal yacht Britannia. A small video camera in a crown on top of the carriage gives the Queen a 360 degree view of the procession.
New Zealand kauri and a bit of one of Hillary's ladders are among 72 small squares that make up the door panelling, with pieces of 10 Downing St and Robert Scott's Antarctic sled.
