I recently went through this dilemma ... my sis and bil were having their 25th Anniversary. They were (luckily) going on a cruise to celebrate. This opened up an opportunity for me. I got them a nice silver 5x7 frame that they could use to put one of their anniversary cruise photos into when they got home. It was perfect (for this situation). They loved it and put their anniversary cruise photo in it when they returned home.
I don't think you necessarily have to go "extravagent" to do "silver". Something simple and nice tends to work every time!
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