Much of the gold stolen in the £26m Brink's-Mat raid of 1983 might have been recovered if police had acted on evidence volunteered just two days after the robbery by Ray and Honor Poulston, who lived next door to one of the men smelting the hoard down near Bath.
But the Poulstons' call to Avon and Somerset police, although it brought a visit from officers, failed to bring any action against the smelting operation, which was not raided by detectives for another 14 months - during which time more than £13m worth of bullion had been smelted to disguise its origin and sold on the open market.
Documents seen by the Independent on Sunday show that Scotland Yard knew of the Poulstons' information during its investigation into the robbery but never acted on it. They were not called to give evidence into the trial of the the man who was smelting gold, a businessman called John Palmer. Mr Palmer, who was charged with complicity in the robbery, admitted smelting gold, but denied knowing it was stolen. He was acquitted.
Not one original gold bar has been recovered since the day in 1983 when masked men burst into a Heathrow warehouse in which the Brink's-Mat security company was storing more than £26m worth of bullion, although property, cash and other assets equivalent to the value of the stolen gold were surrendered after a series of High Court judgements in January which followed an investigation by private detectives acting for a Lloyd's syndicate.
After the robbery Lloyd's offered a £2m reward for information leading to conviction or recovery of the gold. Last month the Poulstons filed a High Court writ against the insurers in which they claimed the reward and disclosed for the first time the extraordinary apparent oversight by police. The writ claims that if their information had been acted on promptly it could have led to recovery of much of the bullion.
The Poulstons now live in the Algarve in Portugal. They emigrated shortly after the Brink's-Mat robbery because, after 20 years running a busy Bath carpet shop, Mr Poulston's health necessitated the move.
At the time of the robbery, they were living in a Georgian mansion divided into flats outside Bath. Their neighbours included a barrister, an accountant and a policeman. Opposite the main building was a coach house.Shortly before the robbery, John Palmer moved into it. "We only saw him once or twice in the driveway," said Mrs Poulston. They only knew that he was something to do with the jewellery trade.
Mr Palmer was, in fact, a director of a Bristol-based bullion company which was later shown to be the front for the re-distribution of the Brink's- Mat gold.
During his trial Mr Palmer claimed that he had left the company but continued to do odd jobs, including smelting, for it. He is now being sued in the civil courts by Lloyd's for recovery of the proceeds of the robbery.
Two days after the raid, on Monday, 28 November, 1983, the Poulstons arrived home earlier than usual. "It was around 5pm," said Mr Poulston. "We heard this screaming noise, like a jet, in the woods. I said to our son: `Go and check what the noise was, will you?' When he came back he said he had seen a hut on Mr Palmer's property with fumes issuing from the roof. He was able to look under the corrugated sheeting and saw a pot, white hot, in the middle of the floor.
"The first thing I said was: `That must be the Brink's-Mat gold!' It had been on the TV. My wife said: `Your mind's working overtime.' But I decided to ring the police."
Shortly afterwards, a panda car drew up at the front door, and two officers from Avon and Somerset Constabulary stepped out. Mr Poulston suggested they go and see the smelting hut for themselves, which they did, following his son's route through the trees. They then thanked him for his help and left. Later they telephoned to say that the hut was just outside their jurisdiction - literally a matter of yards - but that they would pass the information on to the neighbouring police station.
The Poulstons heard nothing more for 14 months, by which time they were in the Algarve. British newspapers reported the raid on Battlefield. "We contacted our lawyers and asked them to apply for the reward," said Mr Poulston. "We assumed they had acted on our information - although it did seem a little late in the day."
But the police had not. They had traced the smelting operation through an entirely different connection.
It emerged, however, in correspondence with the Poulstons' solicitor, that Scotland Yard did know of their evidence. "I confirm that Avon and Somerset constabulary have forwarded to me full particulars of your client's contact with police and I will pass these details to the insurance company concerned," wrote one senior investigating officer, Detective Chief Superintendent Brian Boyce, in 1985. Scotland Yard has never explained why it did not act sooner.
The Poulstons expected to be approached for a witness statement ahead of Mr Palmer's trial in 1987. In that trial, Mr Palmer admitted he had been smelting gold in 1984, but denied knowing it was stolen. He was never challenged over the Poulstons' evidence of smelting the previous year. The Poulstons were neither asked to provide a statement by the police nor to give evidence in court. Mr Palmer was acquitted.
They had, however, already given a statement to insurance loss assessors - but were later told that because the evidence did not lead to a conviction they would not be eligible for a reward.
Their lawyers have issued this month's proceedings on the basis that they were denied the opportunity to claim the reward because the police had apparently ignored their evidence.
Mrs Poulston said that for years the family had feared that their safety could have been at risk: "We did our duty as members of the public. Now we would like to know exactly what happened to what we told the police."