The government of Sierra Leone rejected a $7.8 million bid for a 709.48-carat rough diamond last week, as the stone failed to meet the reserve price, Reuters reported.

The diamond, which artisanal miner Pastor Emmanuel A. Momoh discovered in March, is believed to be the 13th-largest ever found. It drew five offers, starting from $2 million, with the top bid of $7.8 million coming from Belgium-based diamond dealer Ray Diam, the news agency said Friday.

We’ve decided not to sell the diamond today because the highest bid price…does not match the government reserve price,” Reuters quoted Sahr Wonday, chief auctioneer and head of the National Minerals Agency of Sierra Leone, as saying. The government now hopes to sell the stone for a higher price at international auction in Antwerp or Tel Aviv, Wonday added.

The government had already delayed the auction to enable more bidders to take part; the sale was initially scheduled for early April.