An 1880 Japanese gold coin, 16.97 mm in diameter and weighing 3.33 grams, is expected to fetch a record high price of around ¥20 million when the debt-ridden Finance Ministry puts it on the auction block this Sunday.

"The coin is quite rare. Only 87 of them were produced in that year and probably less than 10 of them still exist," said Toshio Takeuchi, chairman of Ginza Coins Co., a noted dealer based in Tokyo's Ginza district.

"Yes, it is said the price can be around ¥20 million or so," Takeuchi said.

The ministry started auctioning its old coins — which are still considered modern — in 2005 as part of efforts to reduce the government's snowballing debt.

In the 12 auctions held so far, 24,500 coins have been sold for a combined ¥4 billion.

The 1880 coin, part of the ministry's last auction, is expected to fetch the highest price of all, said a ministry official in charge of the auction.

"Even the Finance Ministry owns only one. We asked a national association of coin dealers to estimate the value in advance, and it said the price could be around ¥20 million," the official said.

The highest price so far was for an 1877 gold coin, which fetched ¥17 million in an earlier auction.

The 1880 coin's face value is ¥2. It was among a collection of precious metal and coins the ministry held from the time of World War II. The collection was once confiscated by the U.S.-led Occupation authorities after the war but was returned to Japan in 1952 when the 1951 San Francisco Peace Treaty went into effect.

The 1880 coin is well-known among collectors.

When Ginza Coins auctioned one of the same coins in November, it sold for ¥27 million.

Its condition was better than the one the ministry plans to put on the block, according to Takeuchi.