Sterling silver and polymer
Polymer is incredibly tough when properly cured and respectfully treated. But it's not indestructible!
Under normal circumstances any piece of polymer will tolerate anything your skin can put up with. It's waterproof, temperature stable, and colour fast.
When warm, a pure polymer bangle has a very pleasing slight flexibility, which makes it very comfortable and forgiving to wear - a warm bangle (body temperature) will change shape slightly when gently squeezed, making it a bit easier to get on and off. Don't do this when it's cold tho - you will create a split in the material that gets worse with time and can't be fixed.
Sharp items will cut or scratch polymer, and very high temperatures (150 degrees centigrade +) will burn it.
Over time the high polish on some items (especially cutlery or anything that gets knocked around a bit) will start to dull, and the piece might end up with more of a matte or semi-gloss finish.
Silver in polymer pieces will tarnish (like all silver) and a gentle wipe with a silver cleaning cloth will bring back it's shine. Please do not immerse polymer and silver pieces in silver cleaning solution - you may find it destroys the polymer sections!