recommend a silver necklace.
There are three reasons:
1. The coming-of-age ceremony represents a step towards adulthood, and a silver necklace is a good sign of adulthood for girls. It is mature and handsome (especially the chain, it is best to choose a leather rope), which makes them look very confident when facing their 18 years old, and has a style of a young mature woman.
2. Every girl has a princess dream in her heart, and the coming-of-age ceremony is even more meaningful to a girl. I suggest you give a princess crown engraved name necklace. The necklace has a princess crown, which is very noble. If you engrave your niece's name on it, it will look very special.
3. Silver has a good meaning in traditional Chinese culture, especially for girls.
This kind of necklace can be customized online now. You can check it online. Just pass your niece's name to the online customer service.