The Abernethy Pearl or Little Willie as it is affectionately known, was "fished" out of the River Tay in Perth, Scotland in 1967 by William Abernethy. It is known as the most perfectly spherical and largest natural pearl to be found.

The Abernethy Pearl is 43.6 grains or 2825 grams, which makes it as large as a marble. This pearl was produced by a mussel in the Margaratifera margaratifera family. It was originally valued at 10,000 pounds in 1967, but is truly priceless today. 

Perth Scotland was known as the home of the Scottish River natural pearls. Pearl fishermen and women were probably gypsies traveling through the country. Because of overfishing, Scotland outlawed pearl fishing that wasn't under a controlled operation in 1998.

The Abernethy Pearl is on view at the Cairncross Jewelry store in Perth.