The affectionately sweet blue color of blue topaz is bright and airy like the crisp air of winter, which matches the month of December which it represents. In an anniversary band, it is an incredible gift idea for a 4th anniversary between spouses or from a child as a memento of the bond between a parent and a child with a December birthday that is easily stackable against other rings that could represent other members of the family. Choose between platinum, or white, rose, or yellow 14kt or 18kt gold for the metal type for the setting.