Eiderdown is a soft, insulating material made from the down feathers of the Eider duck. These feathers are highly prized for their warmth and lightweight properties, making them ideal for use in bedding and outerwear. Eiderdown is often collected from nests in a sustainable manner, ensuring minimal impact on the birds. Due to its rarity and the labor-intensive process of collection, eiderdown is one of the most expensive types of down available. It is commonly used in high-quality duvets and comforters, providing exceptional warmth without the bulk of traditional materials.