Rare Earth Magnets and Platters

Your best best for both is to sell per piece and not per pound. The platters you should be able to sell as mlcc price at your local yard but they're aesthetically pretty so some folks buy them for arts and crafts. Strong magnets are sellable and it's unlikely their scrap value will ever be higher than a resale value as a usable magnet. If you're lucky you can find someone to buy them a couple for $1 or something. Not sure it's worth the effort imo