Generally, the best anniversary gift is something that has special meaning to the people celebrating the anniversary. However, Hallmark has a list of traditional and modern gifts for each year of marriage.
For the 14th year, the traditional gift used to be ivory but was changed to "animals" to protect the declining elephant population. Some ideas fitting this theme might be a stuffed animal or a special trip to see some exotic animals. The modern gift for the 14th year is gold jewelry. Depending on the tastes of the couple, a gold locket or a gold bracelet may be a good choice for this.