White gold and platinum read similarly at a glance, but platinum is denser and carries a higher percentage of the pure metal by weight; 14kt white gold offers the gold hallmark alongside a bright, cool finish at a different price point.
Visually Speaking
For a pendant gift, orientation affects how the design reads on the body. A centered single bail hangs vertically; an offset bail can create the angled look an asymmetrical piece needs.
The Perfect Gift
Amethyst is worth considering beyond the February birthday context. Sincerity, peace of mind, and protection are the symbolic associations it carries from its ancient history, which provides a gifting vocabulary that makes it appropriate for occasions where personal or sentimental meaning is the point, regardless of when the recipient was born.