A cast-iron bust of Adolf Hitler, hidden in a Yorkshire attic for 60 years, has been donated to Yad Vashem after celebrity antique dealer Andrew Lamberty bought it for £1,000.

But the sinister bronze head, found by British troops during the liberation of Bergen-Belsen, would have been worth £40,000 if Mr Lamberty had decided to sell it on the open market.

Mr Lamberty is one of the dealers on Channel 4 show Four Rooms, which began last week. Experts bid for quirky artefacts from members of the public.

None of the three other dealers would touch the bronze sculpture of the head of Adolf Hitler, brought in by Geoffrey Blackburn, 86, from Mosborough, South Yorkshire.

Retired builder Mr Blackburn said: "It was given to me by a friend who was one of the British troops who liberated Bergen Belsen. The troops went berserk and smashed nearly all of the Nazi memorabilia, but he brought the bust back to England, and he gave it to me.

"His wife wouldn't have it in the house. I put it in my attic and forgot about it. It's been there 60-odd years. But I found it and decided to sell it. I'd like it to go in a museum."

Furniture dealer Mr Lamberty offered to buy the bust for £1 and send it to Jerusalem's Holocaust museum. Mr Blackburn was uneasy about accepting and bartered Mr Lamberty up to £1,000.

Mr Lamberty said: "I didn't want to pay much. I offered to have him work with me to place it in a museum but he wasn't keen so I wanted to get a contract sale which would let me do what I wanted with it. He has his reasons, and I can't speak for him. I don't feel there should be money made on that sort of thing. It would have been worth a lot more. He didn't get market value."

He said the condition of the bust was consistent with Mr Blackburn's story. "If you look at it up close, round the back, you can see where it's been smashed off wherever it was mounted. It must have been hit pretty hard, because it's iron, but the ear and the back of the head have been sheared."

Mr Lamberty said he planned to visit Yad Vashem if the bust ever went on display there. "I would love to go to the museum, it's fantastic architecturally, and friends have recommended it."

Yifat Bachrach-Ron, deputy spokesperson for Yad Vashem, said: "The cast iron head is currently on its way and we believe that the decision by the donor to safeguard it at Yad Vashem is of merit. The bust is not intended for display, but will become part of our vast collections."

Ben Barkow, director of the Wiener Library, which has a large collection of Nazi artefacts, said that it was common for British soldiers to bring back souvenirs from Nazi-occupied Europe.

"Many have ended up in our collection. The problem is that now there's an enormous demand for this stuff," he said.

"There is a lot of fake Nazi memorabilia on eBay. I can imagine the large bust fetching a very high price if it was made by a famous Nazi artist."