Why do they skim the top layer off of boiled gold?

Skimming the top layer off boiled gold, a process often referred to as "dross," is done to remove impurities and unwanted materials that rise to the surface during the melting process. This helps ensure the purity and quality of the final gold product. By eliminating these impurities, refiners can achieve a higher grade of gold, which is essential for various applications in jewelry and electronics. Additionally, this practice enhances the overall aesthetic and value of the gold.