I've only seen the kind in this link.

I gave one to my mother in law a few years ago and she still has it hanging in a tree in the back yard of her townhouse.

Here is a link that might be useful: DIY Silverware Wind Chime

I've never seen them shaped like mushrooms,sounds interesting. I tried to click the DIY link and kept getting "timed out", I'd love to see and get some more ideas. Here are some I've made from silver-plated utensils and trays, beading wire,old glass prisms and glass beads.
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I guess I will add collecting silverware to my "to-do" list! These are great!