Purple duvet cover
Down and Feather. A combination of down and feather is cheaper than pure down. Pure down makes you really warm in winter while down and feather mix is perfect for summer or not-so-cold months.
Wool. This is another type of duvet filling that is natural. A wool-filled duvet will keep you warm during cold months and cool during hot seasons. Most of the time, a heavy wool-filled duvet is warmer than a light duvet.
Synthetic. These are made of polyester fabric and they are probably the cheapest in the market. They are not as comfortable as other types of duvet filling because it will not mold round your body when you lie down on it. A more expensive type of synthetic filling is microfiber. It feels like a down duvet but the similarities end there.
Cotton. This is popular in warm countries where people do not need heavy comforters in cold season. The price is similar to that of wool-filled duvets.
You have to consider these things when choosing a duvet and duvet cover for your bed. It is important to choose the best one if you want to be comfortable while sleeping.