CERN boffins turn lead into gold for about a microsecond at unimaginable cost

So alchemists had the right idea – they just lacked a 27 km particle accelerator

The dream of every medieval alchemist – turning lead into gold – has finally come true thanks to some impractical physics at CERN's Large Hadron Collider.

Physicists at the multibillion-euro atom smasher near Geneva managed to transmute lead into gold during high-speed ion collisions, proving that you can defy nature if you throw enough money, energy, and hardware at the problem. Sadly – if you're an alchemist, and less so if you're a physicist – their golden bounty lasted for about a microsecond and weighed less than a fart in a vacuum.

This glittery miracle occurred not through occult incantations or dodgy tinctures, but by aiming beams of lead at each other, travelling at close to the speed of light. Occasionally, instead of colliding head-on, the ions whizz past each other, close enough for their electromagnetic fields to get frisky. In rare moments of subatomic magic, a lead nucleus gets so rattled it ejects three protons, spontaneously reinventing itself as gold. Transmutation achieved.

The ALICE experiment – CERN's specialized kit for sorting through nuclear mayhem – picked out these atomic wardrobe changes from the mess of debris. Between 2015 and 2018, CERN clocked 86 billion gold atoms emerging from these lead-on-lead encounters, as reported by Nature. That sounds impressive until you realize it adds up to about 29 trillionths of a gram.

In other words, as observed on Bluesky, supposing you "ran the experiment 300 million times, and collected those tiny gold atoms into a big pile, you would have gold with a market value of about a dollar."

Worse, most of the newly minted gold atoms don't hang around long enough to be admired. They smash themselves to bits or disintegrate almost instantaneously.

All the same, the paper [PDF] on the findings, published on May 7 in Physical Review Journals, notes: "The transmutation of lead into gold is the dream of medieval alchemists which comes true at the LHC."

The observations are "the first to systematically detect and analyze the signature of gold production at the LHC experimentally," said ALICE member Uliana Dmitrieva.

While an earlier CERN accelerator achieved something similar two decades ago, this time it was at a higher energy, meaning a higher probability of gold and cleaner observations, said Stony Brook University physicist Jiangyong Jia.

Before you get any ideas about turning CERN into the world's most expensive mint, don't. "Understanding such processes is crucial for controlling beam quality and stability," Jia said – politely reminding everyone that gold is just a side effect, not a retirement plan.

So alchemists were right. Science can turn lead into gold. It just requires 27 kilometers of underground tunnel, a national budget's worth of funding, and the willingness to accept a return on investment measured in atomic particles. ®