Yellow gold pairs beautifully with a variety of gemstones and materials. Common choices include diamonds, sapphires, emeralds, rubies, and other colored gemstones, which can add vibrant accents to the gold. Pearls are another classic choice, creating an elegant and timeless combination. Additionally, materials like onyx, turquoise, and various colored enamels are used to create unique and stylish contrasts with yellow gold in necklace designs. The choice of gemstone or material can greatly influence the overall look and style of the necklace.