The amount of gold mined from Kalgoorlie's famous Golden Mile may never be known according to an amateur historian who recently made a surprising discovery while poring over records.
Retired mining industry veteran and accountant Peter Dillon says he's found the Golden Mile's production was "overstated" by about 10 per cent or the equivalent of 700,000 ounces less than historic records suggest.
At today's metal prices, the shortfall would be worth $1.7 billion.
Mr Dillon, from Perth, has been reviewing Department of Mines, Industry Regulation and Safety records for the Eastern Goldfields Historical Society in Kalgoorlie-Boulder for a research project to define how much gold the area has produced.
He says there's a simple explanation for the discrepancy.
Between 1896 and 1903 the official records counted the amount of bullion produced in mines instead of the ounces of gold refined at the Perth Mint.
The former financial and metallurgical accountant says the bullion was typically 85 per cent gold.
"I couldn't reconcile the numbers that were reported at the mine level with the numbers reported at the state level," Mr Dillon says.
"I thought there is something going on here, there is a real significant difference."
After "weeks of bashing on spreadsheets" the mines department confirmed the numbers reflected the weight of bullion sent from mine sites.
"That is not the fine ounces of gold, which only comes after refining. The smelting process includes traces of silver and copper and other impurities.
"On the Golden Mile, it was about 9-10 per cent."
'Overstated' numbers are significant
The period under review takes in 1903, which is considered the peak year of production on the Golden Mile due to spectacularly high grades of gold resulting in 1.27 million ounces of production.
That's roughly three times what is being mined with modern machinery today.
But Mr Dillon believes the real number for 1903 is closer to 1.06 million ounces.
The state government corrected the mistake in 1906 by changing the way it recorded amounts.
Mr Dillon says while the window was "small", the numbers were "still significant".
Golden Mile's rich history
The Golden Mile has produced more than 60 million ounces, according to its modern owners, since Australia's biggest gold rush was sparked by the discovery of Kalgoorlie 129 years ago.
In August 1893, prospectors William Brookman and Samuel Pearce on behalf of a South Australian syndicate rode into the nearby town of Coolgardie to register the Great Boulder lease.
Within months, the pair had pegged and registered a total of 19 leases.
The term Golden Mile became popular in 1899 and was originally used to describe the mines on the Ivanhoe, Great Boulder, Golden Horseshoe, Chaffers, Hannan's Star and Boulder Main Reef leases.
Nowadays residents refer to it simply as "the Mile" and the term is often used to describe the entire group of leases that make up the Super Pit.
Kalgoorlie 'mile' is unsurpassed
Mr Dillon's connection to the area goes back beyond his work during the early days of the Super Pit to his father who worked underground in the 1930s and '40s.
He says the fact the production records were "overstated" does not take the shine off the Golden Mile's history.
"Today it is still recognised as, if not the greatest ore body of gold on the planet, then it's probably in the top one, two or three," he says.
"The Golden Mile is in fact a bit of a misnomer because everything I've looked at tells me the Golden Mile was actually two to two-and-a-half miles long.
Mr Dillon says he'll never be able to reconcile the amount of gold that was pocketed by pioneer miners who did not want to see all the riches go to wealthy London mining executives.
"I wouldn't say for every ounce that was produced, there was an ounce pilfered, but certainly there was gold pilferage and there was a lot more of it going on in those days," he says.
"The temptation turns honest people into thieves."
