Popular bullion coins - American Eagle and Buffalo

The Coinage Act followed the creation of the new government by the framers of the US Constitution, who realised the need for a monetary system. Prior to this, currency in the US included a mix of foreign and colonial currency, produce and livestock. Alexander Hamilton, Secretary of the Treasury, prepared the plans for a national mint himself.
Today the United States Mint operates six facilities across the US and employs more than 1,600 people.
American proof and uncirculated coins.
Proof coins are specially produced to a much higher standard and were originally intended as
pre-production samples. When coin collecting became popular and the market for high quality, accurate coins grew, most mints began producing larger quantities of proof coins to satisfy enthusiastic collectors.
Uncirculated coins are those that haven’t been in circulation, meaning they’re of the same quality they were in when they were produced. Contrary to popular belief, this doesn’t mean that uncirculated coins will be in pristine condition. They might show contact marks obtained during production.

American Eagle
Gold American Eagle coins are available in both proof and uncirculated finishes. They contain .917 fine gold (22 carat) and are available 1 oz, 1/2 oz, 1/4 oz and 1/10 oz variations.
The American Eagle coin was first produced in 1986 shortly after the purchase of South African Krugerrands became illegal. Following trade limitations caused by apartheid in South Africa, the US government created its own bullion coin to capitalise on the opportunity.
The American Eagle features Augustus Saint-Gaudens’ design of Lady Liberty, which was first used on the Double Eagle from 1907 – 1933.

American Buffalo
Gold Buffalo coins are coins that consist of .9999 (24 carat) gold and carry a $50 (US dollar) face value.
The Buffalo was the first 24 carat gold proof coin ever struck by the US Mint and was first offered to the public in 2001. The top of the range in terms of accuracy, quality and gold content, it’s a widely sought-after coin that appeals to both investors and collectors.
The Buffalo coin features James Earle Fraser’s designs which originally appeared on the 5-cent coin produced between 1913 and 1938 and otherwise known as the ‘Buffalo Nickel’ or the ‘Indian Head’.

 Source: Gold Bullion