"We got talking about skulls and the next day he turned up with this skull. He said it was Ned Kelly's skull, and told me to 'put it in the bottom of your bag and wrap it up'."
Hoffman said she had cared for the remains ever since - one of more than 20 skulls in her collection.
"I have treated it with respect, I haven't lit candles in it or drunk red wine out of it or anything bohemian like that. I don't want to let it out of my possession unless it is his skull."
Kelly, an Australian folk hero, was hanged in 1880 for killing three police officers, but the location of his remains had been a mystery until late last year.
Scientists identified his bones through extensive DNA testing of two dozen skeletons exhumed from Melbourne's Pentridge Prison site, where criminals were buried in mass graves.
Victorian Institute of Forensic Medicine spokeswoman Deb Withers said this week that they were keen to learn more about Hoffman's skull.
"There is a chance that that is his head, although it is a long shot. That would be wonderful if it was.
"It's either out there somewhere or it has disintegrated into nothing."
A DNA sample would be required to prove it either way.
But a forensics expert at Auckland University said the way the skull had had wires attached indicated it had been used in teaching, which made it less likely to belong to the famous outlaw.
Gina McFarlane said it belonged to a young male adult, possibly European. "It could be five years old, it could be 100 years old. The fact that the top of the cranium has been cut off and reattached by wires indicates it's a teaching skeleton."
Kelly's remains were a contentious issue. The bushranger's skeletal pieces identified by DNA have been returned to his descendants after a property developer was forced to hand them over.
Hoffman said she would return the skull to Kelly's surviving family if it was proven to belong to their relative.