The lifespan of rose gold necklaces, like any other jewelry, largely depends on how well they are cared for and the quality of the materials used. High-quality rose gold necklaces can last for generations with proper maintenance. Over time, they may develop a natural patina that can enhance their beauty. Regular cleaning and maintenance, such as polishing and re-plating, can help prolong their lifespan. It's essential to store them properly to prevent tangling or scratching. In general, a well-maintained rose gold necklace can be enjoyed for a lifetime and can even become a cherished heirloom.