Book fair organisers, The Friends of the University of Newcastle, are hoping to track down the owner of a "beautifully preserved" medal commemorating the coronation of King George VI and his wife, Elizabeth, on May 12, 1937.

Life member and former Friends of the University president, Vic Levi, said the medal - and a red, white and blue bow - was found among "thousands" of donated books in its original red box. It was accompanied by two letters - one from Buckingham Palace, and the other from the then Premier of NSW, Sir Bertram Stevens.

"The medal had been awarded, and the letters addressed, to a Miss Elizabeth Mary Legge," Mr Levi said.

"I'll bet there is someone out there who will know something about it.

"We'd love to know why and how she got it too. The mystery is quite absorbing, I think."

Book Fair convenor, Leslie Gent, said they often found treasures buried within the boxes of donated books.

But this medal - very likely an 82-year-old family heirloom - had "almost certainly" been packed with the books by mistake.

"We are hoping someone connected to Miss Legge or her descendents will come forward and claim this precious piece of history," Mrs Gent said. "If not we will offer it for sale with our other rare items."

Among the other items for sale at the 2019 Book Fair is a 100-year pictorial history of Newcastle's Christchurch Cathedral dating from its establishment as a slab building in 1812. There is a miniature copy of The New Testament bible, sent out to British troops in 1914, and a copy of Sun Zi's Art of War, printed in Chinese and English, on pure silk pages.

The Book Fair is to be held at the University of Newcastle's Great Hall from August 3 to 10 from 10am each day.

The proceeds would fund further student scholarships.

"We have invested about $600,000 in scholarships at the University of Newcastle in the past 10 years," Mr Levi said. "We raised $89,000 at the last book fair."

Know something about the mystery medal? Let us know at news@theherald.com.au.