The primary difference between bijoux and fine jewelry lies in the materials used for their creation. The French term bijoux (often called costume or fashion jewelry) is crafted from accessible, non-precious materials such as brass, copper, plated base metals, glass, plastics, and synthetic stones. Conversely, fine jewelry is constructed exclusively from precious metals like gold, platinum, and sterling silver, set alongside certified precious gemstones like diamonds, rubies, and emeralds, making fine jewelry an enduring investment asset while bijoux focus purely on temporary fashion trends.