What is the difference between a duvet and goose down duvet?

I am looking to buy one and I would be better informed before making my purchase. I do not want to end up being dooper by a sales person. Thanks for the help.

duck feathers are generally used in down comforters and less costly and down duvets.Goose are a better option, but usually much more expensive and says someone else, find allergen free materials.

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