South Africa's Single 9 pound (1898)
Price: $4 million
South Africa's Single 9 pound ranks third in the list of the most expensive gold coins. It was released in 1898, although 1899 is considered the actual year of minting. This was the period of the Anglo-Boer War. At that time, South Africa could not make the stamp with the date of 1899, and the authorities had to use the old one with the 1898 number. Later, the local mint started issuing coins with the right date. Coins of 1898 and 1899 years of release received the name 'Single 9'.