Here are some interesting notations about down. BTW, my Scandia down comforter cost quite a bit nearly 20 years ago. It has been a wonderful comforter, and was worth every penny.

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What is down?
Down is a natural substance - the soft plumule or cluster found under the breast feathers of geese and ducks. Down is nature's finest insulator, keeping these birds warm in the frozen climates from Northern Europe to Siberia. Scandia DownŽ uses only White Goose Down & Feathers in all our products.
High quality White Goose Down contains the largest clusters providing the greatest insulation value with the lightest weight possible. White Goose Down and Feathers are the preferred choice in white bedding for their clean appearance in our soft, light cotton tickings.
When the clusters loft in a comforter or garment, they interlock and overlap to trap a protective layer of air that insulates, keeping warmth in and cold out. Down does not produce warmth but it holds the warm air the body creates. The bigger a cluster is, the more still air it can trap to keep you warm. So, generally, the best down is formed by the bigger clusters found on larger, more mature birds.
Here is some more information:
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What is fill power?
Fill power measures the amount of space in one ounce of down.
That's nice, but how exactly do you measure fill power? To measure the amount of space in down, you would take one ounce of down and compress it. When released, the down will expand and fill up a certain amount of space. The amount of space it fills up is normally measured in cubic inches.
So a comforter advertised as 575 Fill Power means that each ounce of down fills 575 cubic inches of space? That's right. And the higher the number of the fill power, the higher the quality of the down. Good comforters normally start out at 575 fill power. Better comforters are 650 fill power and up.
Besides the quality of the down, why else is fill power important? Fill power is what gives down comforters its loft. Also, higher fill power comforters are warmer. Because the down takes up more space, it is able to trap more warmth.
What if I want to buy a comforter with higher quality down but without the extra warmth?
Look for the amount of ounces of down inside the comforter. Some comforters with higher fill powers may have less down than a lower fill power comforter. This is to keep the comforter from becoming too warm.
What is thread count?
Thread count is the amount of threads woven per square inch. To measure thread count, you would count the number of threads contained in one square inch of fabric. The finer the threads, the higher the count will be. Thread counts usually start at 200 threads per inch and go up.
So how does thread count impact my bedding decision?
Well, the higher the tread count, the lighter and more breathable the fabric becomes, and the smoother it is to the touch.
What is a baffled comforter?
A baffled comforter is one that has a vertical wall of fabric joining the upper and lower portions of the shell. Baffles allow the down in your comforter to assume its fullest loft. The higher quality comforters (this also usually translates into the more expensive) are made with baffles. You will be able to identify baffled comforters in advertisements by looking for wording such as "baffled boxes" or "baffle construction". If you do not see wording in a comforter ad that specifically includes the word "baffle" in some form, chances are 99.9% it's not a baffled comforter.
So if it's not a baffled comforter, what is it?
Most likely a sewn through comforter. The majority of comforters are sewn through construction. Unlike a baffle, there is not a vertical wall of fabric joining the upper and lower portions of the shell in a sewn through comforter. Obviously sewn through is a less expensive way to produce comforters and such comforters normally cost less. Sewn through comforters can be very good, especially if they are made by quality manufacturers (all sewn through comforters carried by Comfort House are of the highest quality). You'll just be missing out on the down expanding to its fullest loft as can be achieved with a baffled comforter.