The ear wires are made from a metal called Niobium. This is a surgical metal that is used to implant pace makers for hearts. If it's good for the heart...it's good for the lobes!
A single earring weighs 9.7 grams. If you have a scale that measures in oz or grams, (food scale?), I suggest weighing one of your comfy earrings to see where your weight tolerance is. I can wear these earrings at special dress up events for four or five hours, but they're a wee pit heavy for me to wear all day long.