All that glisters is not gold. In some cases it is depleted uranium.

Three Chinese men found this out when they came across a lump of shiny metal in a scrapyard in Bishkek, in neighbouring Kyrgyzstan, last year. Attracted by its shiny surface and its “gold sparkle”, they haggled the dealer down to a price of $2,000 (£1,135) for what both sides regarded as a treasure but neither could identify.

The men smuggled the 274kg (604lb) object across the border and into China and hid it in the home of the father-in-law of one of the men in the westernmost Xinjiang region.

One thing puzzled them. At night, a report on a local government website said, “they were surprised that, when the lights went out, the treasure sparkled and glittered”. One of the men, identified as Mr Wang, “chipped a piece from it and kept it beside his bed — sometimes playing with it”.

Eager to profit from their investment but ignorant of how to price their find, the men decided to take a chip thousands of miles to Beijing to ask scientists at prestigious Tsinghua University to identify their treasure. Cutting off a chunk of the metal was no easy task and the men broke several saws before they succeeded in getting what they considered a decent-sized piece.

“To prevent the sample being lost or stolen on the way, Mr Wang used tape to stick the unidentified treasure to his body, and it never left him night or day.”

The trio’s hopes of riches evaporated once surprised experts looked at the lump and swiftly determined that it was a radioactive material. They called the police, who detained the men on suspicion of smuggling. It was the first reported case of smuggling of such a banned material into China.

Twice as dense as lead, depleted uranium is the substance left after the most highly radioactive parts are extracted. It is used in armour-piercing ammunition. Contact with the skin is usually not harmful but it can damage kidneys, lungs and other organs if it gets into the body.

The case gave the authorities a conundrum: the law states that only those who deliberately smuggle nuclear materials may be subject to punishment and it was clear that the three men were entirely clueless about true nature of their “treasure”.

Prosecutors decided that there was no case and set them free. So far the men have shown no signs of physical abnormalities, state media said.

Heavy metal

— Uranium is a silver-white, weakly radioactive metal

— In the human body, on average, 90 micrograms of uranium exist naturally

— It is used mainly in nuclear plants, which require the radioactive content to be enriched from 0.72 per cent to about 1.5 per cent. What is left is depleted uranium

— If eaten 98 per cent of depleted uranium will pass safely through the body

Source: World Health Organisation

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