Seasoned prospector Mick Brown, 42, was a couple of weeks into giving up smoking and was getting grumpy so his wife told him to leave the house for some fresh air.

So Mr Brown went prospecting near Wedderburn in an area he had been before.

He started moving across it with his detector when the machine went off loudly over a particular spot. 

Only six inches beneath the surface, Mr Brown hit the top of a gold nugget.

He doubted himself for a moment, thinking it was a "big molten blob of copper". 

"I thought bugger me, it is, it's bloody gold," Mr Brown said. 

"I just dug it up, 87 ounces of the good stuff."

Mr Brown said the nugget was worth about $135,000 but he hopes a private collector will offer more. 

"Sometimes they do say gold is worth twice its weight in gold if it's a really nice looking nugget," he said.

Mr Brown finds his nugget quite attractive and says it has "good grooves and moves".

Asked what he would do with the money after selling the nugget, Mr Brown said he would take his four daughters and wife out for dinner. 

On a more serious note, Mr Brown said he might pay off his tax debt and buy his children a spa bath.

He has named his big find the "fair dinkum nugget" because when people feel its weight they say "fair dinkum this is huge".

Mr Brown said it was silly to be secretive about his nugget and it was better to let people have a hold.

"What am I supposed to do, 'yeah I’ve found a nugget but you can't look at it'," he said.

"It’s cool and it's given everyone a good little rev up."

Mr Brown hopes his good fortune will encourage other prospectors to keep at it and inspire others to try prospecting. 

"There’s more to life than sitting on your (bottom) and watching TV," he said.

"If you put some theory into it, get some books, look at maps, which way and side of the hill it falls, you’re upping your chances of finding it."

Mr Brown tried to get his daughters into prospecting, but they lacked patience. 

"It's a hobby, not just a hobby, it's a skill to read the ground, to distinguish targets and to listen."

Mr Brown moved to Kerang from the Pilbara in Western Australia where he was also a keen prospector. He said it made sense to continue prospecting because other hobbies, such as fishing, weren't possible.

"It's not like we've got the ocean in the Mallee," he said.

Ironically the success of finding a decent nugget took away Mr Brown's motivation to prospect.

"You know how you see, and you go, and you conquer, and then you've conquered and you think 'okay what else can I do now?'. 

But the motivation returned after a couple of weeks.

"There’s some big ten kilo jobs out there," Mr Brown said.