With its earliest known origins dating back to the third millennium BCE. Dating back to 1800 BC, boxing was the ultimate test of strength in a one-on-one sport. The ancient Greeks even incorporated the sport into their Olympic Games thousands of years ago. In modern times, the sport's popularity has continued to grow with fighters such as Muhammad Ali, Rocky Marciano, Floyd Mayweather Jr. and Mike Tyson. The gold coin is made of 9999 fine gold and has a face value of 1 dollar. The edition is strictly limited to just 15,000 pieces worldwide.