1848, the historic anniversary being celebrated this week around Budapest, not only signifies lost opportunity. A new exhibition at the National Museum, where the revolutionary March 15th demonstrations took place 171 years ago, shows another side of the coin. Or rather, three coins, shining illustrations of a tale of untold riches, patriotism and Hungarian achievement.

1848 saw uprisings across Europe – and Hungary, under the Austrian yoke, was no different. On 15 March, Magyar revolutionaries read out poet Sándor Petőfi’s patriotic Nemzeti dal and their 12 demands for freedom from Vienna. On the other side of the world, news had just reached America’s Eastern seaboard of the discovery, that January, of a few gold nuggets at Sutter’s Mill in California.

Back in Budapest, the demonstrations led to the first Hungarian government – but then war on several fronts and, ultimately, defeat.

Their uprising quelled, certain high-ranking Hungarian officers sought their fortunes elsewhere. A select few found it in the Gold Rush that would sweep across America, and change the face of California forever.

Now a unique exhibition – at the same National Museum of 1848 lore – tells their remarkable story in the shape of three gold coins. Although long part of the museum’s permanent collection, they recently came into focus when exhibition curator Dr Csaba Tóth was musing on their value.

Already familiar with the story behind them, a stirring drama now unveiled for the public to discover, Dr Tóth contacted one of the top coin graders in America, Florida-based NGC, which has a submission centre in Munich. So impressed was NGC with Tóth’s tale that they offered to assess the items for free.

Taking the coins with him, and two bodyguards, Dr Tóth was amazed to find that not only were they judged to be in prime condition – 63 on a scale of 0-70 – but had a collective worth of some £500,000.

So how did they wash up at the National Museum?

At the time of the Hungarian Uprising, Transylvanian Count Sámuel Wass was a Member of the new Hungarian Parliament. With the revolution in full swing, Wass toured Europe, then America, in search of weapons for beleaguered Hungarian forces. Finding himself in New York, he made the acquaintance of fellow Magyar revolutionaries Gustáv Molitor and Károly Uznay. Setting his heart on a career in shipbuilding, Wass changed tack when news came of the California Gold Rush. He and his companions duly set off for San Francisco.

By then, 300,000 desperate souls from all corners of the globe had the same idea. Boats crammed the little harbour at San Francisco, a hamlet of 200 people in 1846, a boom town of nearly 40,000 by 1852. With no railroad or direct steamships, travel there was treacherous, either overland across thousands of miles of disease- and bandit-ridden country or through the jungles of Panama – the famous canal only opened in 1914.

If they survived the journey, the migrants arrived to find the Wild West, tens of thousands huddled in makeshift wooden shacks created from broken-up boats, no rule of law and no health care. The so-called forty-eighters, those who rushed here in 1848, made thousands of dollars a day. For the estimated 90,000 forty-niners, it was dog eat dog. California itself only came into being in 1850. And still the boats arrived…

Wass and Molitor decided against claim-jumping and panning. Instead, with their ingenuity and engineering experience, they set up a metal refinery and a mint. Lucky prospectors may have found flakes and nuggets after weeks of back-breaking work, but they then needed to turn that treasure into coin.

With no US mint west of New Orleans, over in San Francisco, few coins were in circulation and so to ease commerce, private mints sprang up. Stamping them ‘Wass, Molitor’ and using a design similar to the eagle and head of Liberty as featured on regular US currency in the east, the Hungarians issued gold coins for denominations of $5, $10, $20 and $50, large sums of money at the time.

Thousands of dollars flowed through the company every day. Wass and Molitor became very rich men. In their own way, they were early Hungarian pioneers in the New World, forging a path later graced by Hollywood filmmakers and award-winning scientists who escaped chaos and danger at home to succeed in their particular fields.

One fine California morning in 1855, patriotic to a fault, Count Sámuel Wass dropped four of his gold coins into an envelope and dispatched them to the National Museum in Budapest. By now, steamship companies such as Pacific Mail were in operation and the package safely arrived in Budapest.

The gold nuggets and other precious goods Wass also sent were later destroyed when fire swept Budapest’s Natural History Museum during another Hungarian revolution, in 1956. A decade or so before, Soviet soldiers had rampaged through the National Museum, torches in hand, in search of vodka. When they didn’t find any, a number of priceless artefacts were damaged beyond repair.

It is doubtful whether any of the gold coins ended up in the pocket of a Red Army uniform – when a complete inventory of the museum collection was taken in 1966, only one of the four coins was missing. Mystery surrounds the fate of Wass’ elusive $20 gold piece.

Amazingly, after two world wars, a brutal uprising and half a century of Soviet dictatorship, three Wass gold coins survive to this day. Mounted and back-lit in a display case, they centrepiece the California Gold exhibition in a lower-floor room of the National Museum. Alongside is an accountant’s log, transactions recorded in elegant black handwriting, a hefty volume Wass may have brought back with him when he came home in 1858.

A member of the Academy of Sciences, Wass served his newly semi-autonomous nation in many ways. Most of all, he managed to fulfil his dream and put his talents to good use at Hungary’s first steamship company.

Hungarian National Museum District VIII. Múzeum körút 14-16

Open: Tue-Sun 10am-6pm California Gold runs until 28 May