Olympic medals belonging to great Australian swimmer John Konrads will appear at auction later this month.
The 69-year-old's 1500-metre freestyle gold medal from the 1960 Rome Olympics, the only Olympic gold he won, is expected to sell for AU$15,000 to $25,000 at Leski Auctions in Melbourne on August 18.
It was stolen from Konrads's home in 1984 but recovered when an attempt was made to sell it in 1991.
Latvian born Konrads, along with sister Ilsa, was instrumental in advancing the sport of swimming; setting 26 individual world records during the 1950s and 1960s.
A bronze medal from the same Games, awarded to Konrads for the 400m freestyle, will also feature with an AU$8,000-$10,000 estimate; evidence of the difference in value collectors attach to lesser medals.
The 110-collection also includes diaries and log-books.
Sports memorabilia collectors can capitalise on the relevant lack of funding many athletes receive, which ensures that a steady stream of medals from recent Games hit the market at tempting prices.
"Money is a big consideration for those athletes," auctioneer Ingrid O'Neil told America's ABC News.
"A few thousand dollars to a Russian athlete is very important and a lot of money. It reflects on the conditions some athletes have to endure."
A gold medal won by a Greco-Roman wrestler at the 1984 Los Angeles Games recently sold at an Ingrid O'Neil auction for $8,000.
For the most historic medals - those that have a significant story behind them - the asking prices can really shoot up.
The gold medal won by Mark Wells of the US ice hockey team in 1980 made $310,700 at Heritage Auction Galleries in 2010, far above its $100,000 estimate.
It was the first time a medal from the "miracle on ice" side had appeared at auction.
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