Each anniversary that a couple pass after their wedding day is traditionally marked by a certain material. From paper at the first, to diamond at the 80th, convention states that gifts for the couple should be made of, or constitute, the material associated with the length of their relationship. If you're looking for a traditional gift for a couple who tied the knot six years ago, give them something containing candy, iron, wood or amethyst.
Buy a ready-made iron sculpture or commission an artist to produce one for the couple. Make the subject of the sculpture personal to the people you're buying it for. If they're musicians, go for a sculpture of the instruments they play. If they love sports, incorporate this into the piece. Adding these personal touches to a traditional gift will show that you've gone that extra mile.
Although considered a rather common gift, beautifully presented chocolate or candy is a way to adhere to the traditions of anniversary gift giving in the sixth year of marriage. Rather than simply grabbing a box of sweets off the shelf at a candy store, consider visiting a chocolatier to discuss producing something personal and individual for the couple.
Buy the couple a piece of wooden furniture or an ornament made of wood. You might also consider buying them a bonsai tree or a small tree for their garden. The latter is a particularly poignant idea as the tree will grow as the couple age and will serve as a constant reminder of the longevity of their relationship.
Visit a jeweller and inquire about amethyst rings or necklaces. Each year of marriage is associated with a stone, amethyst being representative of the sixth year. If you can't find anything suitable, commission a jeweller to make something special. To tie in with another traditional material for the sixth anniversary, ask to have an amethyst stone set in iron.