YGO TCG: Maximum Gold - Rules of Play says:
Premium Gold Rares are the ultimate evolution of the Yu-Gi-Oh! TRADING CARD GAME Gold Rares. Golden outlines and borders cleanly accentuate and enhance the art you love and add texture to the cards. Symbols like Level stars and Attribute icons shine like pools of precious molten metal. Premium Gold Rares inspire awe in the hearts of any Duelist who sees them, and Maximum Gold gives you the chance to add 52 of Dueling's finest cards to your Decks as beautiful Premium Gold Rares!