Tens of thousands of people attended last week’s Diamond Jubilee Concert outside Buckingham Palace – but one Calne company got closer to the action than most.

Calne Engineering, which has been based at Porte Marsh Industrial Estate for the past 35 years, was commissioned to make the beacon which was set alight by the Queen to mark the end of the weekend of celebrations.

The contract has been a closely-guarded secret, with the company agreeing not to disclose the design of the beacon before its show-stopping part in the proceedings.

Mark Board, managing director of Calne Engineering, said: “The company that installed it, Back Stage Technologies, are actually based in Calne and they were initially asked to make the beacon a couple of years ago.

“But, with the recession hitting, the government decided it didn’t want to be seen to be spending money on something like this.

“Then they found a private investor to fund it and they came to us with some provisional drawings and gave us four weeks to make it, which was a bit hectic.

“We made it and it was then erected on the Saturday before the concert, but it was kept under wraps all along.”

The beacon was a giant diamond fashioned from precision laser-cut steel plate. It had an additional four facets to create a diamond with 60 faces – one for each of the Queen’s years on the throne.

It stood 8.5m high when mounted onto a plinth and took Back Stage Technologies two days to put in place in the centre of The Mall adjacent to the Jubilee Concert stage.

Mr Board, who has headed the company for the past two years, said: “It is an extremely prestigious thing to have been involved in.

“I am quite a royalist myself, I like the royal family.

“So when the opportunity came along, we jumped at the chance.

“I was there to watch it all being put together and I was so delighted with it. It was a real honour to make it for them.”