In the 17th c the techniques to clean down were developed and down, and down became a precious resource. The Eider Down is dried, sorted and cleaned by hand using methods passed down through generations.About 75% of the eiderdown worldwide comes from Iceland and Icelandic eiderdown is considered to be of the highest quality.Eiderdown has unique properties that give it very powerful insulating effects, despite being one of the lightest materials known to man. Because of its unique properties, it is considered to be the best insulating material that can be used to make duvets and comforters.