In 1929 Lasseter began writing to various federal and state politicians claiming that decades earlier, he had discovered a rich gold bearing reef in Central Australia, with gold “as thick as plums in a pudding”. Lasseter claimed he had travelled to the area in the search for rubies and had stumbled upon the gold reef.

The lure of gold at the time of the Depression inspired enthusiasm from many quarters and the Central Australian Gold Exploration (CAGE) Company was formed with John Bailey as Director, lending support to Lasseter’s claims that a vast gold reef existed in Central Australia. Lasseter was employed as guide and was paid 5 pounds a week. 

During the expedition, Lasseter kept to himself, writing in his diary and sleeping apart from the group in the cabin of the truck. Doubts formed in the minds of expedition members that there ever was reef, that instead, it was a figment of Lasseter’s imagination. Lasseter had no knowledge of the areas they travelled through and was vague on the location of the gold reef.

After falling out with the rest of the expedition members, Lasseter continued on alone and claimed in his diary that he had rediscovered the reef and had pegged and claimed the area but gave no date or no location.

Some of the Aboriginal people in the area cared for Lasseter during his last days, providing food and company. Lasseter drew pictures in his diary to amuse them and made attempts to learn their language. There are references to them in this letter fragment.

Living in South Sydney in the 1920s, Lasseter worked for a brief time on the construction of the Sydney Harbour Bridge and had worked as a carpenter in Canberra building the first Parliament House. During the Great Depression, labouring jobs in Canberra and on the Harbour Bridge were employment projects for unemployed men.

The discovery of Lasseter's letter is featured in Warren Brown’s new book, Lasseter's Gold.